I've been a little obsessed with chocolate turtle flavored things lately. I had a to-die-for turtle fondue the other day, which made me seriously consider getting a chocolate fountain for my kitchen. Because, you know, sometimes you just need turtle fondue for dinner. By yourself. In your pajamas. Since I can't afford a chocolate fountain nor do I want chocolate stains all over my pajamas, I settled with making a turtle cake. I diverged from the standard cake, which can often be covered in a sickening amount of chocolate and caramel syrups. Instead, I put the caramel flavor in a buttercream icing, which separates three moist chocolate cake layers, and topped the cake off with a deliciously bitter dark chocolate ganache. Leaving the sides of the cake open not only allows the beautiful layers to show through, but also decreases the amount of icing, showcasing the richer flavors of the cake.
The Science.
While I was researching for this post, I came upon a recent study that investigated the chemical components of caramel. As a baker and a scientist, I got so excited I literally squealed at my desk. Since most of you probably don't "nerd out" quite as hard as I do, I'll summarize the findings for you. Caramel is made by heating sugar with butter until it becomes brown and thick, and this change in color and flavor represents a variety of chemical reactions that are occurring within the mixture. In a nutshell, the scientists found that three things happen when sugar turns into caramel: the sugar compounds link together to form long chains of sugars, water is released as a byproduct, and aromatic compounds are created, which give the caramel its distinctive color and smell [1]. Now, a lot of people have trouble making caramel because sugars have a small temperature range within which they caramelize, and above that range they burn. This is why so many fancy candy thermometers and manufactured and sold. However, this caramel icing recipe doesn't require a thermometer, since the ring of bubbles around the edge of the saucepan indicate when the caramel is ready [2].
The Recipe.
Chocolate cake:
2 cups sugar
2 cups flour
1 1/2 teaspoon baking powder
1 1/2 teaspoon baking soda
1 teaspoon salt
1 cup boiling water
1 cup dutch cocoa
2 eggs
1 cup milk
1/2 cup vegetable oil
1 teaspoon vanilla
Preheat oven to 350°F. Spray 3 8-inch round baking pans with baking spray, and line with waxed paper. If you've never lined cake pans before, see the post for Almond Nutella Cake for pictures. In a medium bowl, combine sugar, flour, baking powder, baking soda, and salt. In a small bowl, dissolve cocoa in boiling water to allow it to "bloom." In a large bowl, beat together egg, milk, oil, and vanilla. Add dry ingredients and beat on medium speed for 2 minutes. Stir in bloomed cocoa. Divide batter equally between the cake pans, and bake on center rack for 20 minutes. Cool cakes in pan for 10 minutes, then invert onto wire racks to cool completely. Once cool, peel off the waxed paper. If your cake layers are "crowned" or rose unevenly, you can press them down as I described here.
Caramel Icing:
1/2 cup salted butter
1 cup brown sugar
1/2 cup 40% heavy cream
1 teaspoon vanilla
2 cups powdered sugar
Melt butter and brown sugar in a large saucepan over medium heat, stirring constantly. When bubbles form around the edges of the pan, stir in the cream. Continue heating until bubbles form once more. Pour caramel into a large bowl and gradually beat in powdered sugar. Set bowl over an ice bath and continue to beat until cool and fluffy, about 5 minutes.
Chocolate Ganache:
4oz bittersweet bar chocolate
1/4 cup 40% heavy cream
1/4 cup chopped pecans (for topping)
Place chocolate and cream in a microwave safe bowl. Gently heat in the microwave for two 30 second intervals, stirring inbetween. Be careful not to overheat the chocolate, or it will seize and you will have to start over. Once the chocolate beings to melt, stir constantly until the cream is completely combined. If it begins to separate, you can add 1 tablespoon of melted butter to bring it back together. Keep ganache slightly warm and spreadable until you are ready to put it on the cake.
Assembly:
Place the first cake layer upside down on a cardboard cake round. This allows you to frost the underside of the cake, which is flatter and doesn't crumble as much. Using a spatula, cover the cake with one third of the caramel icing in an even layer. Repeat this step for the next two layers.
1. Golon, A and Kuhnert, N. "Unraveling the Chemical Composition of Caramel." Journal of Agrig. and Food Chem. 2012. Vol. 60(12), pp 3266–3274.
2. Galvin, Lori et al. Best of America's Test Kitchen. Brookline, MA: America's Test Kitchen, 2009.
