How to Make Chocolate Cake with Chocolate and Peanut Butter Frosting

True to Dennis’s genuine love for all things chocolate and all things peanut butter, we made a chocolate cake with chocolate and peanut butter frosting for his birthday.

Okay, I’m actually using the pronoun “we” here very loosely.  It was more like “he” rather than “we”.  Dennis made his first two-layer chocolate cake from scratch and I was the assistant pastry chef and food stylist.  We used a basic chocolate cake recipe from Alice Waters’s The Art of Simple Food and a chocolate butter icing recipe from The Joy of Cooking.  We tweaked the icing recipe a little to make a decadent chocolate and peanut butter frosting instead.  The chocolate cake recipe is a great versatile recipe that can be used to make cakes in any format from sheet cakes to cupcakes.

For the chocolate cake, makes one 9-inch one-layer or multilayer round cake

4 oz unsweetened chocolate
2 cups cake flour
2 tsp baking soda
1/2 tsp salt
6 Tbsp cocoa powder
8 Tbsp (1 stick) butter, softened
2-1/2 cups brown sugar
2 tsp vanilla extract
3 eggs, at room temperature
1/2 cup buttermilk, at room temperature
1-1/4 cups boiling water

For the chocolate and peanut butter frosting, makes two cups of frosting

4 oz unsweetened chocolate, coarsely chopped
3 Tbsp unsalted butter
1/4 cup milk
1/2 cup peanut butter
1 tsp vanilla extract
3 cups confectioners’ sugar, sifted

Making the cake

Preheat the oven at 350 degrees F.

Butter two 9-inch cake pans and line the bottom with parchment paper. Butter the paper and dust the pan with flour or cocoa, and shake out the excess. Lining the pan with parchment paper makes removing the cake from the pan much easier.

Coarsely chop the unsweetened chocolate.  We used the Venezuelan chocolate El Rey Bucare that has 58.5% cocoa.  Place the coarsely chopped chocolate in a metal bowl and set the bowl over a pot of simmering water. The metal bowl should be big enough so that it sits on top of the pot without touching the water.

Turn off the heat. Stir the chocolate from time to time until completely melted and smooth. Remove the bowl from the pot and set aside the melted chocolate.

Sift together the cake flour, baking soda, salt, cocoa powder.

In a large bowl, beat the softened butter until creamy. Beat the butter either by hand or in a stand mixer. Beat in the brown sugar and vanilla extract. Then beat in the eggs, one egg at a time. When fully blended, stir in the melted chocolate. Add half of the dry ingredients to the mixture and combine. Stir in the buttermilk. Then stir in the rest of the dry ingredients. Gradually pour in the boiling water until completely blended. The batter will have a thin liquid consistency.

Pour the batter equally into the two cake pans and bake for 45 minutes or until a toothpick inserted into the center comes out clean. Place the pan on a cooling rack and allow the cake to cool completely.

Run a knife around the edge of the pan to loosen the cake. Remove the cake from the pan and peel off the parchment paper. The cooled cake can be kept in the pan and stored if you are not using the cake the same day. Just make sure that it is tightly covered.

The recipe can also be used to make a sheet cake or cupcakes. For a sheet cake, prepare a half-sheet pan as mentioned above. Pour the batter, smooth the top, and bake for about 20 minutes. For cupcakes, bake for about 30 minutes. The recipe makes around 24 individual cupcakes.

Making the icing

Melt the chocolate the same way as previously. Place the coarsely chopped chocolate in a metal bowl and set the bowl over a pot of simmering water. Remove from heat. Add the unsalted butter, stir in the milk and the vanilla extract. Blend by hand or use a stand mixer. Gradually add the confectioners’ sugar and beat until smooth and spreadable. Add the peanut butter and mix until well blended.

Add more sugar, if needed, to thicken the consistency. According to the Joy of Kitchen, confectioners’s sugar icings tend to thicken on its own if left undisturbed for a few minutes. Also, it thickens if stirred over a bowl of ice water. Add more peanut butter if you prefer a more peanut buttery taste.

Make the icing just before using.

Assembling the Cake

Place the first layer on a cake pedestal. Using a carving knife, trim the top of the first layer to make it flat.

Evenly spread a generous layer of the icing on top of the cake using a metal spatula. Then place the second layer on top of the frosting.

Generously coat the cake with the frosting using a metal spatula. The recipe for the frosting makes 2 cups, which we found to be just enough for a two-layer 9-inch cake.  If you prefer a cake more lavishly coated with frosting, adjust the ingredients proportionally to yield more.

The cake was amazing.  Rich and moist.  Dennis’s birthday, too was equally amazing.  Sweet sixteen.