Chocolate-Peanut Butter Fun Cake

Hold on to your hats, people, because this is one fantastic cake (recipe originally from Bon Appétit). I absolutely loved it! The chocolate cake itself is moist and flavorful, rich without being too heavy, and would even be good on its own or with another icing. The Engineer, who likes to drink milk with good desserts, said, “It’s like there isn’t enough milk in the world for this cake. It’s awesome.” This is one we’ll definitely make again!

My icing was a little runnier than I expected, but I attribute this to the Texas heat. I could have put it in the fridge a bit before spreading it, but it wasn’t absolutely necessary. I actually ran out of cane sugar while making the icing, too, so I topped it up with coconut sugar, but it was delicious.

For the chocolate cake
1 ¼ cups all-purpose flour
1 cup sugar
¾ cup natural unsweetened cocoa powder
1 ½ tsp. kosher salt (I used a scant 1 tsp. table salt)
1 tsp. baking soda
¼ cup vegetable oil
1 tsp. vanilla extract
1 ¼ cups water
½ cup finely chopped semisweet or bittersweet chocolate (3 ½ oz.)

For the peanut butter buttercream
½ cup sugar
¼ cup egg whites (from about 2 large eggs)
1 ½ tsp. vanilla extract
¼ cup creamy peanut butter
6 Tbsp. (¾ stick) chilled unsalted butter, cut into 1/4-inch cubes (you could also use frozen margarine)
kosher salt
¼ cup chopped semisweet or bittersweet chocolate (about 1 ¾ oz.)
¼ cup chopped unsalted, dry-roasted peanuts

For the chocolate cake
Preheat oven to 350 °F. Coat bottom and sides of an 8-inch square pan with nonstick spray; line bottom of pan with parchment paper. Whisk flour and next 4 ingredients in a large bowl. Add oil, vanilla, and water; whisk until smooth. Fold in chopped chocolate. Scrape into prepared pan; smooth top. Bake until a tester comes out clean when inserted into center, 35–40 minutes. Let cool completely in pan on a wire rack.

For the peanut butter buttercream
Combine sugar and egg whites in a medium metal bowl set over a saucepan of simmering water. Whisk constantly until sugar dissolves and mixture is hot to the touch, 3–4 minutes. Remove from heat; using an electric mixer, beat on high speed until cool and thick, 5–6 minutes. Beat in vanilla, then peanut butter. With mixer running, add butter a few pieces at a time, beating to blend between additions. Season with salt.

Run a thin knife around pan to release cake. Invert cake onto a serving plate. Spread peanut butter buttercream over top. Garnish with chopped chocolate and peanuts.