The peanut butter filling couldn’t be simpler. It’s peanut butter. Seriously. Spread it on the cake while it’s still warm, and the peanut butter will make a lovely, tasty layer between the cake and the icing.
I love this kind of icing. It’s simple to make, so that’s always a plus. And, it’s so soft and gooey. It goes on the cake while it’s warm, and then it hardens and sets as it cools. It forms some kind of serious shield over the cake. Don’t be alarmed if the icing cracks and crinkles when you cut into it. That’s just the nature of this kind of icing. If it bothers you, that’s why some very smart person invented garnishes.
What You’ll Need
* For the cake:
* 2 cups all-purpose flour
* 2 cups granulated sugar
* 1 teaspoon baking soda
* 1 cup unsalted butter
* 1/4 cup unsweetened cocoa powder
* 1 cup water
* 1/2 cup buttermilk
* 2 large eggs, lightly beaten
* 1 teaspoon vanilla extract
* 16 ounces (about 1 & 1/2 cups) creamy peanut butter
* For the icing:
* 1/2 cup unsalted butter
* 1/3 cup buttermilk
* 1/4 cup unsweetened cocoa powder
* 16 ounces confectioners’ sugar, sifted
* 1 teaspoon vanilla extract
How to Make It
* 1 _ Preheat oven to 350°. Grease and flour a 9” x 13” baking pan.
* 2 _ Whisk together flour, sugar, and baking soda in a large bowl. Set aside.
* 3 _ Place butter in a medium saucepan. Melt over medium heat.
* 4 _ Stir in cocoa powder. Then, stir in water, buttermilk, and eggs. Continue cooking over medium heat, stirring constantly, until the mixture boils.
* 5 _ Remove the mixture from the heat and add to flour mixture. Stir until smooth. Stir in vanilla.
* 6 _ Transfer batter to prepared pan and spread evenly.
* 7 _ Bake 20 to 25 minutes, or until a pick inserted into the center of the cake comes out clean.
* 8 _ Cool in pan on wire rack for 10 minutes. Then, spread the peanut butter over the cake. Allow to cool completely.
* 9 _ To make the icing, place the sifted confectioners’ sugar in a large bowl. Set aside.
* 10 _ Combine butter, buttermilk, and cocoa in a small saucepan. Cook over medium heat, stirring constantly, until the mixture begins to boil.
* 11 _ Remove from heat and pour over confectioners’ sugar. Stir until smooth. Stir in vanilla.
* 12 _ Spread icing over peanut butter. The cake can be served immediately or can sit at room temperature to allow the icing to set.
