This Where the Wild Things Are Birthday Cake is perfect for the wild things in your life. The chocolate cake and salted caramel buttercream make the perfect celebration cake. The chocolate tree bark texture is an easy technique that looks super realistic and also tastes super delicious.
Line a 9x3-inch cake pan with parchment, and spray it with nonstick cooking spray. If you don't have a 9x3 inch pan, three shorter 9-inch pans can be used. Preheat the oven to 350 F.
Add the butter and both sugars to the bowl of a large stand mixer fitted with a paddle attachment. Beat them together on medium-high speed, until light and fluffy, about 5 minutes. Add the eggs one at a time, beating well after each addition. Add the vanilla extract and mix it in.
In a separate bowl, whisk together the buttermilk, sour cream, and water (or coffee, if using). In a different bowl, sift together the flour, cocoa powder, baking soda, and salt. With the mixer running on low, add a quarter of the sifted flour mixture. When the flour streaks have almost all disappeared, add a third of the liquid to the mixing bowl. When that’s incorporated, continue to add the drys and wets in an alternating pattern, ending with the dry ingredients.
When the dry ingredients are nearly incorporated, stop the mixer. Scrape down the bottom and sides of the bowl with a rubber spatula, and finish mixing the cake by hand. Pour the batter into the prepared pan and smooth it into an even layer. Bake the cake for 55-60 minutes, until a toothpick inserted into the center comes out with just a few moist crumbs attached. Cool the cake completely before using. The cake can be made several days in advance and kept, well-wrapped and refrigerated or frozen, until ready to use. If you freeze it, make sure it's partially defrosted before you use it so you can cut it easily.
To Make the Salted Caramel Filling:
Combine the butter, brown sugar, corn syrup, sweetened condensed milk, and cream in a medium saucepan over medium heat. Stir while the butter and sugar melts. Once the mixture comes to a boil, insert a candy thermometer.
Continue to cook, stirring frequently to keep the caramel from scorching, until it reads 236 F on the candy thermometer. Remove from heat, stir in the vanilla and salt, and quickly pour it into another bowl to stop the caramel from cooking. Press a layer of cling wrap on top, and refrigerate it until thickened and chilled. Salted Caramel Filling can be made several weeks ahead of time and kept in the refrigerator until ready to use.
Note that this recipe makes a little more than you will need, and you will probably have some filling left over. It keeps in the refrigerator for several weeks, and is great on toast or ice cream.
To Make the Buttercream:
Combine the egg whites and the granulated sugar in the bowl of a large stand mixer, and whisk them together. Choose a small saucepan that lets you fit the base of the stand mixer snugly into the top of the saucepan—this is your makeshift hot water bath. (Alternately, you can use a different bowl or an actual bain marie and then transfer the mixture to a mixing bowl once it’s heated.) Add an inch of water to the bottom of the saucepan, and bring the water to a simmer.
Place the mixing bowl on top of the saucepan, making sure that the bottom isn’t in contact with the water, and heat the egg white mixture. Whisk frequently so that the egg whites don’t cook. Continue to heat the whites until they are hot to the touch, and when you rub a bit between your fingers, you don’t feel any grittiness from the sugar. Once the whites are hot, transfer the mixing bowl to your mixer and fit it with a whisk attachment.
Beat the whites on medium-high speed until they are no longer warm to the touch—feel the outside of the bowl, and make sure that it is around room temperature. Depending on your mixer and the temperature of your environment, this may take 15-20 minutes, or more. Reduce the speed to medium-low and add the softened but cool butter in small chunks, a tablespoon at a time, making sure to wait in between additions. It may separate or look a little gloopy at this point—fear not. Once all of the butter is added, increase the speed again and whip until it comes together and is light and fluffy. If, after 5 minutes, it hasn’t come together, refrigerate the mixing bowl for 5-7 minutes, to cool the mixture down, and whip it again. Add the salt.
Divide the mixture in half, and to one half, add the caramel sauce, mixing until it is well-blended. Melt the chocolate in the microwave in 30-second intervals, and cool to room temperature. Add the chocolate to the remaining half of the buttercream and mix it in. The buttercreams can be made in advance and kept at room temperature if you’re going to use them the same day, or refrigerated. If they have been chilled, let them sit at room temperature until soft, then re-whip them to get the fluffy texture back before you use them.
First, make the chocolate curls. Melt 8 oz of the chocolate candy coating in the microwave, stirring after every 30 seconds to prevent overheating.
Pour the melted chocolate out onto a large sheet of parchment, and spread it into a thin layer. Place another sheet of parchment on top, and smooth it out with your hands. Working from the long end, roll the parchment up into a cylinder, and secure it with a rubber band. Refrigerate it until the chocolate coating has set completely. Once set, unroll the parchment—the chocolate will shatter into curled shards as you unroll it.
Using a large serrated knife, cut the cake into three even layers. Place one layer face-up on a cake cardboard.
Scoop some salted caramel buttercream into a pastry bag fitted with a 1/2-inch round tip. Pipe a ring of buttercream all along the edge of the cake round to act as a barrier and make assembly neater. Scoop about 2/3 cup salted caramel filling into the center, and spread it in an even layer until it covers the cake and reaches the buttercream ring. Spread a layer of salted caramel buttercream on top of the caramel filling. Top the cake round with a second round, and repeat the process of piping a ring of buttercream and spreading the caramel filling on top. This time, top with a layer of chocolate buttercream instead. Add the last cake layer on top.
Spread some buttercream along the sides and top of the cake in a very, very thin layer—this is just to hold the crumbs in. Refrigerate the cake until it's firm, at least 45 minutes.
Once firm, go back and add another thick layer of buttercream on the outside of the cake. It doesn't matter if you use chocolate buttercream, caramel buttercream, or a mixture of both, and it doesn't matter if it's perfectly smooth—it will all be covered in the end anyhow.
Press your chocolate shards into the sides of the cake, letting the top shards extend a little ways past the top. They should be close to each other, but the occasional small space between chocolate curls is fine. Once the chocolate is applied, refrigerate the cake again to firm up the buttercream and chocolate.
Melt the remaining 8 oz of chocolate coating in the microwave. Use a pastry brush to brush the melted chocolate onto the sides of the cake. Cover every surface liberally, and don't be afraid to go back and add a second layer if it looks thin in spots. Once the sides are covered, pour a small amount of chocolate on top of the cake and spread it to the edges, so all of the buttercream is covered. Refrigerate the cake to set the chocolate completely.
Finally, brush some cocoa powder in random spots on the sides of the cake to give it the look of dusty tree bark. Your cake is finished! Store it in the refrigerator, but for the best taste and texture, allow it to come to room temperature before serving.
To make the cake shown in the pictures, you will need to triple the quantities here, except the salted caramel recipe—that can be doubled. Assemble each cake separately on its own cake cardboard, and chill them well before you stack them. When you stack them on top of each other, use large boba tea straws or big dowels to separate each layer: place one in the center of cake, and four in a ring around it a few inches from the edge. Cut the straws or dowels so that they are flush with the top of the frosted cake, then stack them one on top of each other, and decorate as described in the recipe.The chocolate cake recipe is adapted from Ina Garten’s Barefoot Contessa at Home. The Salted Caramel Filling is from Cake Central.