Oh My Goodness!!! This has to be one of THE richest cakes I have ever eaten. This might rank right up there with the nine layer chocolate cake with chocolate ganache frosting at The Metropolitan Grill. You will definitely need a glass of milk, maybe even two, with a slice of this baby. If you love chocolate and peanut butter then you will think you have died and gone to heaven. If you only tolerate chocolate and peanut butter then you should probably just look and appreciate but move on to another recipe.
With the above being said, this cake was a little over the top for me. I can definitely handle the chocolate but I think the peanut butter pushed me over the edge. If I could just nibble a bite here and a bite there I was fine, but when I had to eat it as a slice I think I went into a sugar coma. So, when (yes, I said when not if) I make this again I will make a regular chocolate cake and use the chocolate peanut butter frosting. It was just a bit too much to have the peanut butter candies in the cake and in the frosting and on top of the frosting. It also made it difficult to slice neatly when you have big chunks of peanut butter cup throughout the cake.
The most difficult part of baking this cake had to have been unwrapping the over two and a half pounds of miniature peanut butter cups! And just look at how messy this cake is when you are putting it together. Yikes! But oh so fun to lick off the fingers when you are finished. Grab a glass of milk and enjoy!
Peanut Butter Cup Cake
1 devil’s food cake mix (or your own chocolate cake recipe)
1 cup buttermilk
1/2 cup vegetable oil
2 cups chopped peanut butter cups (plus more for garnishing – I used almost a 2 pound bag)
8 oz. dark chocolate, chopped
1 cup heavy cream
1/2 cup peanut butter
Preheat oven to 350 degrees. Coat two 9-inch cake pans with cooking spray. Line with wax paper and coat paper.
In a large bowl, beat cake mix, eggs, buttermilk, and vegetable oil on low for 30 seconds. Increase speed to medium-high, beat for 2 minutes. Scrape down sides after 1 minute. Fold in 2 cups of the chopped peanut butter cups.
Pour batter into pans as bake for about 30 minutes or until toothpick inserted in center comes out clean. Cool cakes completely.
Place chopped dark chocolate in a medium bowl. Bring cream just to a boil and then pour over chocolate. Whisk until chocolate melts. Add peanut butter and whisk until smooth.
Trim each cake layer so the top is flat. Place one layer on a wire rack and pour 1 cup of frosting on top. Spread evenly with a spatula. Place second cake layer on top and pour remaining frosting over top and sides of cake. Smooth out with a spatula.
Gently press remaining chopped peanut butter cup pieces all over the top and sides of the cake. (Reserve larger chunks for top and smaller chunks for side – they tend to slide off if they are too heavy).
Place in refrigerator about an hour to set. Remove and serve.