Makes 20 servings
2 cups water
Softened unsalted butter for pans
4 cups all-purpose flour, plus more for pans
4 cups granulated sugar
1 1/2 cups cocoa powder
1 tablespoon baking powder
1 tablespoon baking soda
1 tablespoon salt
4 large eggs
2 cups whole milk
1 cup vegetable oil
2 tablespoons vanilla extract
• Preheat oven to 350°F. In a saucepan over high heat, boil water. Butter and flour four 10-inch and two 8-inch round cake pans. Combine the sugar, flour, cocoa powder, baking powder, baking soda, salt, eggs, milk, oil, and vanilla in a stand mixer and beat on medium speed until smooth. Pour in boiling water and mix immediately on low speed.
• Divide batter among prepared baking pans and bake for 25 to 35 minutes, until a toothpick inserted into centers comes out clean. Allow to cool for 10 minutes before removing from pans. Immediately wrap in plastic wrap and refrigerate until chilled and ready to assemble.
1 cup (2 sticks) unsalted butter, melted
2 cups smooth peanut butter
6 cups confectioners’ sugar
1 teaspoon salt
2 teaspoons vanilla extract
• Cream together butter and peanut butter in a stand mixer until smooth. Add confectioners’ sugar, 1 cup at a time, and beat on medium speed until stiff peaks form. Add salt and vanilla and beat until incorporated.