This recipe is one of those happy little accidents, born out of a moment of experimentation. I intended to make a simple chocolate cake with peanut butter frosting… but when it came time to frost it, my inner demons told me “mix nutella in with the peanut butter. Do it I say!” I’m not in the habit of ignoring commands from my tummy, so I went with it. I’m glad I did.
I used a basic buttermilk chocolate cake recipe, inspired by two of my favorite recipes by Magnolia Bakery & Katie Lee
Joel. I don’t make sheet cakes very often, because they seem sort of inelegant to me. Honestly, it’s silly that I feel that way, because sheet cakes are just as tasty as layer cakes. I think this recipe has helped me get over my sheet cake bias. It is so simple and quick that I think it will become a staple for when I need to bring something to a pot luck or shin dig.
2 sticks of unsalted butter
1 cup buttermilk
1 cup water
1/2 cup cocoa powder
2 cups all-purpose flour
2 cups sugar
1 tsp baking soda
1/2 tsp kosher salt
2 large eggs
1 tsp vanilla
2 cups creamy peanut butter
1 1/2 cups Nutella
Preheat the oven to 350 degrees. Line a 9x12x2 cake pan with parchment and butter the parchment. (If you’re using a glass baking dish, the parchment isn’t necessary, but do be sure to grease the pan well).
In a medium sauce pan over medium-high heat. Combine butter, cocoa powder, water & butter milk. Stir frequently and scrape down the sides of the saucepan to prevent the milk from scortching. Remove from heat once it starts to bubble.
In a large bowl combine flour, sugar, baking soda and salt. Whisk to combine well. In a small bowl gently beat eggs and vanilla. Add eggs & vanilla to the flour mixture, then slowly pour in the chocolate/butter mixture. Mix till well incorporated, then pour into your prepared pan.
Bake for 20-25 minutes or until a cake tester comes out clean.
In a small bowl combine peanut butter & nutella until smooth. Put it directly on the cake when it is still very warm from being in the oven. Smooth the frosting all over the cake, it will get very melty and gooey and deliciously easy to spread. Allow the cake to cool completely on the counter, then transfer to the fridge to help the frosting set up (should take about an hour).