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Classic Chocolate Cake. This recipe makes a two layer 8-inch cake or a three layer 6-inch cake. It is frosted with a simple chocolate American buttercream and decorated with rainbow sprinkles.

Classic Chocolate Cake

Classic Chocolate Cake with simple chocolate American buttercream.
Yield: two 8-inch cake layers or three 6-inch cake layers
Prep Time: 20 mins
Cook Time: 30 mins
Assembly: 30 mins
Total Time: 1 hr 20 mins
Course: Dessert
Cuisine: American
Keyword: birthday, chocolate, cake, easter, buttercream
Servings: 10 slices
Author: Maryanne Cabrera


Chocolate Cake:

  • 2 cup (260 g) all-purpose flour
  • ½ cup (40 g) unsweetened cocoa powder *
  • ½ Tablespoon instant espresso powder
  • 1 teaspoon baking powder
  • 1 teaspoon baking soda
  • 1 teaspoon kosher salt
  • ½ cup grape seed oil, or vegetable oil
  • 1 ¼ cup (250 g) granulated sugar
  • 2 large eggs, room temp
  • 1 teaspoon pure vanilla extract, or vanilla paste
  • cup (150 g) whole milk, room temp
  • 1 cup (240 g) sour cream, room temp

Chocolate American Buttercream:

  • 2 cup (450 g) unsalted butter, softened, room temp
  • 6 cup (680 g) confections sugar
  • 1 cup (80 g) unsweetened cocoa powder
  • ½ teaspoon kosher salt
  • 8 Tablespoon whole milk


Chocolate Cake:

  • Preheat oven to 350°F. Line three 6-inch cake rounds or two 8-inch cake rounds with parchment paper. Lightly grease and set aside.
  • In a large bowl, whisk together flour, cocoa powder, espresso powder, baking powder, baking soda, and salt. Set aside.
  • In the bowl of a stand mixer fitted with a paddle attachment (or using an electric hand mixer), beat together oil, sugar, eggs, and vanilla until well combined.
  • On low speed, alternate adding dry flour mixture and milk. Add about 1/3 of flour mixture. Mix on low speed until almost incorporated. Follow with 1/2 of milk. Mix on low speed. Repeat adding another 1/3 of flour and then remaining 1/2 of milk. Scrape down bowl as needed to ensure thorough mixing. Add sour cream and remaining 1/3 of flour. Mix on low speed until there are no longer any streaks of dry flour.
  • Divide batter among prepared cake pans. Level batter. Bake for 25-28 minutes until toothpick inserted in center of cake comes out clean. Rotate cakes midway through baking to ensure even cooking.
  • Allow cake to cool in pan for 5 minutes. Run mini offset spatula around perimeter of cake to loosen from pan. Unmold cake. Let cake layers cool to room temperature on wire rack.

Chocolate Buttercream:

  • In the bowl of a stand mixer fitted with a paddle attachment (or using an electric hand mixer), cream butter until smooth. Add confectioners' sugar, cocoa powder, salt, and milk. Mix until buttercream is smooth.


  • Level cooled cake layers, if desired. Place one cake layer on cake stand or serving place. For 8-inch cake: spread about 1 ¼ cup chocolate buttercream over cake. (see notes for 6-inch cake).
  • Place second cake layer on top. Spread another 1 ¼ cup buttercream on top. Spread a thin layer of buttercream around the sides of cake to seal in the crumbs (crumb coat). Place in the fridge and allow to chill for 15-30 minutes to set buttercream.
  • Coat cake with final thicker layer of buttercream.
  • Fit a piping bag with a medium or large star tip. Fill bag with any remaining buttercream. Decorate the top of cake with piped star boarder. Garnish with sprinkles as desired. Store cake in the fridge until ready to serve.


Ingredient Notes:
  • I used natural cocoa powder from King Arthur Flour. I also recommend the unsweetened cocoa powder from Trader Joe's. Other cocoa powder options includes: Dutch-processed cocoa or black cocoa. These will produce slightly different results.
  • Instant espresso powder highlights and intensifies the chocolate flavor. You may omit if you cannot find this ingredient. 
  • Canola oil, vegetable oil, or melted coconut oil can be used in place of grapeseed oil. Melted butter can also be used, but will result in a less moist cake. 
Assembly Notes:
  • For 6-inch cake: use about 3/4 cup buttercream for layers.