Ingredients
1 box (18.25 ounces) devil’s food cake mix
3 eggs
1 cup buttermilk
1/2 cup vegetable oil
2 cups chopped chocolate-covered peanut butter cups (about 8 ounces) for the cake, plus more to garnish (I used about 2.5 bags of Reese’s Peanut Butter Cups total)
8 ounces semi-sweet chocolate, chopped
1 cup heavy cream
1/2 cup creamy peanut butter
Preparation
Heat the oven to 350 degrees F. Coat two 9-inch round cake pans with nonstick cooking spray. Line with wax paper and coat the paper with more spray.
In a large bowl, beat the cake mix, eggs, buttermilk and vegetable oil on low for 30 seconds. Increase the speed to medium-high; beat for 2 minutes, scraping down the side of the bowl after 1 minute. Fold in 2 cups of the chopped peanut butter cups. Divide the batter between the prepared pans. Bake for about 34 minutes, or until a toothpick inserted in the center comes out clean. Let the layers cool on a wire rack for 15 minutes. Then turn out the cakes onto the wire racks and cool completely.
While the cakes are cooking, place the chopped chocolate in a medium-size bowl. Bring the cream just to a boil and pour over the chocolate. Whisk until the chocolate melts and then add the peanut butter and whisk until smooth.
Trim the top of the cake layers flat with a serrated knife. Pour about 1 cup of the frosting on top of the bottom cake layer; spread evenly with a spatula. Top with the remaining cake layer. Pour the remaining frosting over the top, allowing it to spill over the sides. Smooth the top and sides with a spatula and then place the chopped peanut butter cups on the top and sides of the cake. Take special care when placing the Reese’s on the sides of the cake as they may slide off at first. Simply press and hold them on the cake for a few seconds. For the sides, I started lining the Reese’s on the bottom of the cake and worked my way up. Refrigerate for 1 hour to set.
