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Killer Rats Cake

Killer Rats Cake

by Barbara Jo

May 2005


Killer Rat Cake

The Killer Rats Cake was made for Son of Zombiefest, our celebration of the posting of our 300th review. Actually, to be fair to the rats, I don't really know that they killed the man they're eating. It's possible that they simply came upon the severed arm and decided it would make a tasty snack. That's why I referred to it through much of this process as the Rat-Arm Cake, but Barbara May pointed out, and I agreed, that was a very uninspiring title, so The Killer Rats Cake it became. Like its illustrious predecessor, The Zombie Cake, The Killer Rats Cake began life as a pattern for a carved pumpkin. Both the pumpkin and the cake depict a severed human arm being devoured by three large, ugly rats. Well, ugly in their cake incarnation, at any rate; they're sort of cute on the pumpkin. The cake arm was constructed in layers, from the inside out, so that a slice of the cake looked like a cross-section of an arm, complete with ulna, radius, bone marrow, skin, etc. Admittedly, this did not make for a spectacularly dynamic presentation, at least as compared to the cakes that burned or shot blood or secreted bodily fluids, but I think it was just as effective, in its understated fashion. Sometimes even I opt for subtlety and finesse over gaudy drama.

Because the cake was created in several separate segments, then assembled, I'm going break up this narrative accordingly, although in reality these processes were occurring simultaneously.

Killer Rat Cake

The Rats

The first step in constructing the rats was to make the gum paste and fondant pieces that needed time to dry before they could be attached to the cake. I did this about five days before the party.

The rat ears are simply gum paste, rolled very thin, then cut into the shape of ears. I then thinned the edges even further with a ball tool and pinched the bottoms together to give the ears the appropriate shape.

Sculpted rat heads

The rat faces were a much more difficult proposition. As I always do, I started by finding a few good research photos to work off of. Of course, I couldn't find any pictures of rats that were as mean as I wanted my rats to be, so I supplemented the photos with the use of a really ugly, vicious, battery operated rat toy that I once bought for Barbara May at a KB Toys that was going out of business.

I made the rat faces out of a fifty-fifty mixture of gum paste and fondant. At first I had a lot of trouble sculpting them because I couldn't figure out how to handle them and set them down without distorting the features I had already carved. Eventually I discovered that I shouldn't try to pick them up, just set them on wax paper, noses facing up, and work on them that way. After that, things went much more smoothly and, with the help of various gum paste sculpting tools and a lot of shortening to keep the gum paste-fondant mix moist enough to work for the requisite period of time, I was able to crank out three pretty vicious looking rat faces, two with open mouths, one with mouth clenched as if he were in the process of ripping off a succulent morsel of flesh.

rat base

The next step was to cut a foam core base for each rat, which obviously necessitated my planning the body shape and position of each rat, so I would be able to stick the base to the cake, then carve around it.

carved rat body

Finally it was time for the actual cake. Barbara May was kind enough to bake the cakes for me. We used a red velvet cake recipe so the rats would look nice and meaty inside, and we started with three 10" round cakes. I then took each cake, leveled the top and split it into two layers using a cake leveler. Cutting each of these layers in half along the diameter of the circle allowed me to assemble the four resulting pieces into a four layer cake shaped like a semi-circle. I used buttercream icing as my filling between layers.

Once I had torted and filled all three cakes in that fashion, I was ready to carve, which is one of my favorite parts of the cake construction process. I started with the first cake upside down and stuck the foam core base to it with buttercream icing. Using a small, sharp kitchen knife I cut the cake so that it was about half an inch larger than the base all around, then flipped the cake sight side up. I then did the more detailed carving, rounding the body, giving the rat haunches, and cutting the front carefully so that the head would line up properly.

airbrushed rat

Having carved all three cakes, I was ready to attach the heads, which I did using buttercream icing, reinforced with a toothpick stuck between then back of the head and the front of the cake. I then frosted the rats with buttercream icing. I took two layers of icing, with some dry time in between, to cover most of the red in the cake.

Before adding fur, I used my cake airbrush to put a base coat of color on each rat. I planned to make one white rat, one brown rat, and one grey rat. For the white rat I used a pink base coat with some darker red and orange shadows. For the brown rat, I used a reddish-brown base, but left some lighter pink highlights. For the grey rat, I used a medium grey base, but with lighter grey and pink highlights. Then I decided that I wasn't satisfied with them, so I airbrushed in even more shadows and highlights.

kitchen ready for spun sugar

The next step was the application of fur, which was made of spun sugar. I had decided, after a few experiments, for the sake of time to make all the fur colorless, then airbrush on the colors. Using Jacque Torres's recipe for spun sugar, I set up two long wooden spoons hanging over the edge of the counter, wrapped half the kitchen in plastic bags, then proceeded to fling hot sugar absolutely everywhere.

Because my spun sugar tools had a tendency to get gunked up and need to be washed after only five or six uses, it was good that I had two. One was a whisk with the curved ends cut off; the other was a wooden ruler with some cut up pieces of wire taped to it. The wire ends of either tool were dunked into a bowl of hot sugar, then whipped back and forth over the two wooden spoons, leaving a trail of thin strands of sugar behind. I then scooped up these thin strands and draped them over the rat bodies. After I had finished the first rat, I decided I had put too much fur on it, so I did less fur on the other two. As it turned out, I was wrong. The first rat, the one with more fur, wound up looking better than the other two.

grey rat

Airbrushing onto spun sugar turns out to be a tricky operation because the sugar is so thin that it tends to dissolve if it gets wet. Long story short, I oversprayed the rats and the two with less fur wound up looking patchy and diseased. I rationalized this by saying that the scene took place in some kind of abandoned government lab which was full of all sorts of chemicals and viruses and the like. No wonder the rats are diseased! The rat that I thought had too much fur wound up looking really good.

brown rat

Before applying the final coat of airbrushed color, I stuck ears to each rat, by simply jamming the bottoms of the ears into the cakes. I obviously should have attached them better, because several of them fell off and later had to be reattached.

pink rat

There are details too delicate to the airbrushed onto cake rats, so I went in with a little brush to paint the insides of mouths and ears and eyes and noses. I also gave little white royal icing teeth to the one rat whose mouth remained open. The other rat that was supposed to have an open mouth settled somewhere along the line and wound up with a closed mouth. The third rat, of course, had a closed mouth to begin with.

The rats still needed, feet, tails, and bloody snouts, but that had to wait until they were positioned on the cake base, so I'll cover that in the Assembly section, which means we're ready to move on to the arm.

The Arm

To begin with, I needed a picture of an arm to work from. I couldn't use my own arm as model, because I wanted a big, hairy man arm. So I turned to my brother-in-law, Barbara May's husband, who was a very good sport about me photographing his arm and incorporating it into the cake.


The first step was to make the fingernails out of gum paste. My brother-in-law has much flatter, squarer fingernails than I do, so it took me a while to get the hang of them and to find an appropriately curved surface to drape them over to dry. I also discovered that the key to sculpting realistic fingernails is the subtle, vertical striations. Take a close look, you'll see what I mean.

skin test

I wanted to experiment with the skin before trying it on the real cake, both to find a good skin texture and because I hadn't used the airbrush much before and I wanted to make sure I knew how to handle it. So I rolled out some fondant and tried texturing it by pressing on it with various fabrics. The winning texture came from a blue dishtowel. I then made a couple of samples complete with protruding veins and let them dry before practicing airbrushing on them.

On the extras of one of the Lord of the Rings DVDs I saw a special effects guy explaining how the way to get a realistic skin coloring on a mask was to work outwards form the inside, that is, start with the veins, and build up the color in layers from there. So I tried it. I started by painting in blue and purple veins, then built up layers of reds, browns, yellows, pinks, and eventually white highlights on top. I think it worked pretty well, except that I need to learn some patience and let each layer dry completely before I do the next one.

arm bones drying

Next came the bones. The bones of the hand are made from hard candy, colored with white and a bit of yellow and brown food coloring. I poured it onto a silpat mat into the shape of finger and hand bones, making many more than I needed, so I'd be able to mix and match the appropriate ones.

I wanted to make the arm bones out of white chocolate, but I had trouble getting it to set up properly, so I wound up using candy melts instead, which really don't taste as good. For molds for the bones I wrapped acetate paper into thin cones. I filled these with melted candy, then dumped then candy out, leaving only a thin coating on the inside of the acetate. I needed hollow bones, of course, in order to fill them with marrow. I then set them upside down to dry, stuck through holes in a Fat Tire Amber Ale box that was sitting on a wire mesh, so excess candy could still drain out of them. Once that layer of candy dried, I repeated the process to build up thicker walls. Once they were dry it was easy to cut the bones to the correct length with a little patience and a serrated blade. Before filling them with marrow, I plugged up the smaller ends with royal icing.

The marrow inside of the bones is made of lemon curd, which Barbara May made for me. If you haven't had it, it's kind of like a super-intense lemon pudding, and we thought it would have just the right consistency for jiggly bone marrow.

After just a few seconds in the microwave, the lemon curd was soft enough to put into a piping bag and pipe into the hollow arm bones. I also put a little fresh raspberry sauce (basically just raspberries pureed with a bit of sugar and lemon juice and strained to remove the seeds) into the piping bag because I thought that bone marrow should have some red in it. Once each bone was full, I plugged the other end with royal icing as well.

hand being assembled
the hand drying

Assembling the bones of the hand took some doing. I built a form out of foam core to assemble the hand on in order to get the somewhat tented shape of a relaxed hand, then draped wax paper over that. One by one I selected bones and stuck them together by melting the ends with one of those big red lighters. Worried that this wouldn't be stable enough, I then piped royal icing over the top of the bones. In retrospect, I should perhaps have just made the bones out of royal icing in the first place. In any event, I should have given the royal icing more time to dry, because the hand wound up collapsing somewhat under the weight of the fondant skin and turned out flatter than I had hoped.

beginning of arm assembly
arm structure

The actual meat of the arm is made of a jelly roll cake, which was easy to cut into appropriate pieces and to wrap around the arm bones. The first step in assembling the arm was to stick a layer of cake onto the previously cut foam core base for the arm, using red currant jelly. I then slathered on another layer of red currant jelly and positioned the arm and hand bones. I added yet another layer of royal icing to the hand at this point, both to attach it to the arm bones and to give it a little more thickness and dimension. Then came another layer of red currant jelly, then more jelly roll cake and even more red currant jelly. I wanted to make sure the arm looked nice and red inside when it was sliced.

the naked arm

skinning the arm

I was finally ready for the nerve wracking process of skinning the arm. Or would it be unskinning the arm, since skinning usually means to remove the skin? Anyway, this was quite scary because effective skin needs a lot of subtle sculpting and texturing, but there is very limited period of time in which the fondant is still workable before it dries out. Gamely, I rolled out the fondant, and draped it over the arm. I covered the arm itself with plastic wrap to keep it moist and started with the hand, carefully trimming and pinching around the finger, adding veins and knuckles and pushing the gum paste fingernails into the soft fondant. I worked as quickly but as carefully as I could, so I could turn my attention to the arm itself. I made veins, protruding from the skin, running the length of the arm and then swiftly grabbed my blue texturing dishtowel. I was almost too late. The texture didn't come out as prominently as I had hoped, because the fondant had dried beyond the ideal texturing point, but I did get some good skin texture in places. I was content. I also pulled and frayed the skin at the back of the arm to give it that all-important violent torn away look.

airbrushing the arm

Next step - coloring. Again, the build up from the purple-blue veins all the way to the white highlights. I clearly didn't learn my lesson last time because again I failed to allow sufficient dry time between coats, which resulted in a few runny spots. I cursed myself and added some brown and purple shadows to cover the imperfections.

The hair making process has been amply discussed in the Rats section, so suffice it to say that I carefully draped the arm hair in the appropriate direction, in some places almost hair by hair. Again, I overairbrushed a little when I went to make the hair brown, but at least it stuck the hair firmly down to the arm. Finally, the fingernails required some brush painting to get the subtle coloring just right. Take a look at your own fingernails; they're more complicated that you think!

And here we will leave the arm for a little while, while I move on to the base.

completing the airbrushing

The Base

Obviously, it would not be very fitting to simply plop a severed arm down on a cookie sheet and call it done. No, I needed a more appropriate base. I decided to go with a sidewalk - simple enough not to distract from the central composition of arm and rats, large enough to give ample room for bloody piping gel rat footprints, apt yet non-specific enough to allow the viewer to construct the scenario of his or her choice around this glimpse of carnage.

I bought a sheet of 3/8" foamcore, figuring that the standard 3/16" foamcore that I use for the cake bases wouldn't be sturdy enough to support that many rats. After carefully studying the sidewalk in front of Barbara May's house, I was ready to begin. First, I made the grout line between two sidewalk squares with some light grey icing and a large scooped decorating tip.


I mixed three different colors of royal icing to use for the small round rocks embedded in the concrete. Using two different sized round decorating tips for each color I piped dots of icing them squished them down and simultaneously textured them with a damp rag. This took much longer than I expected it to, but eventually I had a good coverage of small rocks, which had to dry before the next step.

I used a modified run in icing technique for the concrete. I made two shades of grey icing and watered them down just a bit, so they were easy to spread, but not as thin as regular run in icing. I filled a pastry bag with both colors at once to get a nice random variation of color and attached a wide, flat tip. I used the bag to fill in icing around each rock, then used a knife to spread icing in the larger areas. This took much longer than I had anticipated and I was soon cursing myself for making so many stupid little rocks.

Once that layer of icing had dried it was time to paint. In order to maker the sidewalk look distressed and dirty I went in with some black food coloring and painted stains, mostly around the grout line and around the edges. A thin black ribbon glued around the perimeter of the foamcore finished off the edge nicely.

At this point I'm in a position to describe for you the dramatic conclusion of my cake making saga, but I'm going to pause for moment and go off on a few tangents describing a few other culinary marvels of our party. Hopefully, this will heighten the tension for you and make my eventual return to the cake itself all the more enjoyable.

The Cupcakes

Barbara May and I were concerned that The Killer Rats Cake might not be sufficient to feed all our guests, which is exactly the opposite of the problem that we usually have with my cakes. As it turned out, we needn't have worried (we had two whole rats left at the end of the party) but to guard against the possibility of insufficient cake we decided to make supplemental cupcakes. Barbara May came up with the brilliant idea of making them monster cupcakes, covered in fur, with googly eyes.

cupcake eyes

Several days in advance Barbara May piped a selection of royal icing eyes onto wax paper with lots of different expressions - angry eyes, sad eyes, scary eyes, surprised eyes . . . Once they were dry she painted in little black food coloring irises.

While she was making the red velvet cakes for me to carve into rat bodies she also made several dozen red velvet cupcakes and iced them with the cream cheese icing that traditionally accompanies red velvet cake.

grey cupcake guy
blue cupcake guy

While I was making spun sugar for the rat fur and the arm hair I also made fur for all of the cupcakes, just scooping up a wad of spun sugar and plopping it atop each cupcake. Have you gathered yet that there was a lot of spun sugar involved in this entire operation? Barbara May and I did our best to clean it all off of the kitchen floor, walls, cabinets, etc., not to mention our shoes, but it wouldn't surprise me if she were still finding ants embedded in elusive deposits of sugar in various corners of her kitchen. And you should have seen the weird looking mess when we put our shoes outside on the porch because they were too sticky to leave in the house and the sugar on the soles melted in the heat into gooey, sticky puddles!

group of cupcakes

Anyway, once the cupcakes all had fur I sprayed them various bright colors with my airbrush and turned them back over to Barbara May to stick eyes on to. Interestingly, many of the cupcakes had entirely different facial expressions depending on the side from which they were viewed. Some seemed angry from one angle, but worried from another angle or alarmed from on side, but sad from the other. And they all looked like the bastard children of Muppets and those aliens from Critters.

All in all, they were delicious, cute, and incredibly sticky to eat. Clearly a winning combination!

The Truffles

The final culinary element of our party that I'm going to discuss here is the googly-eyed truffles. Mom had just given up about twelve pounds of fancy chocolate, so we decided to try out some new truffle recipes - brandy truffles, jasmine truffles, ginger truffles, and mint truffles. All the recipes involved soaking various things in cream for various periods of time then pouring the hot cream over chopped chocolate. This mixture is then stirred until smooth and set aside, wrapped in plastic, to cool.


The nest step is to form the centers, which turned out to be much harder than we had anticipated, since the consistency of the chocolate was, well, inconsistent. But we persevered and soon, after letting the centers sit for a bit to dry, Barbara May was ready to dip them all one by one into melted chocolate, an operate that requires non-sweaty hands and a lot of patience, but also satisfies the little girl inside all of us who liked to make mud pies. (Barbara May and I actually mud pie recipe books. Mom still has them in the scrapbook.)


In order to make the truffles appropriate to the horror theme of the party and to integrate them with the cupcakes, Barbara May then decided to give them all googly eyes with little dabs of white chocolate and even smaller dabs of dark chocolate for irises. This had the dual beneficial effects of making the tray of truffles just cute as the dickens and allowing our guests to distinguish between truffle flavors by the direction the eyes were looking. I don't remember which eyeball direction corresponded to which flavor, but one flavor was looking up (or down), one was looking to the side, one straight ahead, and one flavor was cross-eyed!

OK, are you all ready? Take a deep breath because it's time to return to the final chapter of The Killer Rats Cake saga! That's right; it's finally time for the assembly.

The Assembly

the arm in the fridge

So here I was, the day of the party with three rats perched on the counter and a human arm safely stowed away in the refrigerator. Moving everything into place on the base was a risky operation, especially for the hand, which wasn't entirely supported by the foam core base of the arm. But with my natural manual dexterity, a flat spatula, and Barbara May standing by to peel wax paper off the bottoms of the rats, the transfers were all accomplished successfully. The rats lost a bit of hair off their butts when the wax paper was removed, but I stuck most of it back on and, as they were all sort of scruffy and patchy already, it made little difference.

closeup of the rat pulling some flesh off the arm
close-up of the rat biting the arm

I chose to position the rat whose mouth had remained open prominently at the end of the hand, about to chow down on the middle finger. The rat whose mouth had closed against my will I shoved up into the wrist area, so its nose was nuzzled up to the arm. I left some space between the arm and the rat with the clenched mouth so that that I was able to cut a bit of the flesh of the arm and pull out a piece of skin to put in the rat's mouth.

closeup of the rat tails
another rat taking a bite of the cake

Now, as we all know, a rat is nothing without a nice icky tail, and since I was going to exceptionally gross rats, I made them exceptionally long, slimy tails. I made the tails out of fondant, rolled into long strands, then segmented with a plastic fondant tool. Making the tails at this late stage, with fresh, soft fondant, allowed me to drape them grotesquely over the arm and around the other rats. I think the tails really unified the piece.

While I had the fondant out I also make little feet for the rats. I then painted the tails and the feet with some paste food colors and water, varying the colors slightly from rat to rat, but mostly using reds, pinks, browns, and black.

killer rats cake

Now, my composition was complete except for the blood. No severed arm lying on a sidewalk could be complete without copious amounts of spilled blood, so I busted out the piping gel and the red food coloring. Piping gel doesn't really taste all that good; it's just gooey sugar, but it has a great wet, glossy sheen to it. I mixed some that was a nice, deep, blood red and put it in a piping bag with a small round tip. I did the detail work first with this - little bloody rat footprints, and a blood trail from one of the rats' tails that spelled out, of course, "They're coming to get you, Barbara." I also made sure to get blood in and around each rat's mouth and into the fresh wound in the side of the wrist. Then I slathered lots of blood around and on the torn stump of the arm, washed the slimy red goo off my hands, and went to look for a cold beer.

theyre coming to get you barbara, written in blood

cutting the arm cake
cross-section of the arm

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