3 cups granulated sugar
1 1/2 cups unsweetened cocoa powder
1 tablespoon baking soda
1 1/2 teaspoons baking powder
1 1/2 teaspoons salt
4 large eggs
1 1/2 cups buttermilk
1 1/2 cups warm water
1/2 cup vegetable oil
2 teaspoons vanilla extract
Nutella Frosting:
1 (8-ounce) package cream cheese, softened
1/2 cup butter, softened
1 1/2 cups Nutella
1/2 cup sour cream
5 cups powdered sugar
Preheat oven to 350 degrees. Butter and flour 3 9-inch cake pans. Using a stand mixer, mix together flour, sugar, unsweetened cocoa powder, baking soda, baking powder, and salt on low speed until combined. Add eggs, buttermilk, warm water, vegetable oil, and vanilla and beat at medium speed until blended, about 1 to 2 minutes. Divide batter evenly among the three pans. Bake for 30 to 35 minutes or until a toothpick inserted in the middle comes out clean. Cool in pans for 10 to 15 minutes and then remove cakes from pans and place on wire racks to cool completely. Make frosting. Beat cream cheese and butter until creamy. Add Nutella and sour cream and beat until combined. With mixer on low, beat in powdered sugar 1 cup at a time. Scrape down the sides of the bowl and then turn speed up to medium-high for about 10 seconds to make sure everything is evenly blended.