Chocolate Mousse Cake

Total Time Prep: 40 min. + chilling Bake: 20 min. + cooling
Yield 16 servings
Test Kitchen Approved
A towering cake filled with mousse? Sign us up! Learn how to make a four-layer chocolate mousse cake to get your cocoa fix.

Ingredients

  • 3/4 cup butter, softened
  • 1-1/2 cups sugar
  • 1 large egg
  • 1 teaspoon vanilla extract
  • 1 cup buttermilk
  • 3/4 cup sour cream
  • 2 cups all-purpose flour
  • 2/3 cup baking cocoa
  • 1 teaspoon baking soda
  • 1/4 teaspoon salt
  • FILLING:
  • 8 ounces semisweet chocolate, chopped
  • 2 cups heavy whipping cream
  • 1 teaspoon vanilla extract
  • GANACHE:
  • 16 ounces semisweet chocolate, chopped
  • 1/2 cup butter, cubed
  • 1-1/2 cups heavy whipping cream

Directions

  1. Preheat oven to 350°. Line the bottoms of 2 greased 8-in. round cake pans with parchment; grease paper. In a large bowl, cream butter and sugar until light and fluffy, 5-7 minutes. Beat in egg and vanilla. Combine buttermilk and sour cream. Combine flour, cocoa, baking soda and salt; add to creamed mixture alternately with buttermilk mixture, beating well after each addition.
  2. Pour into prepared pans. Bake until a toothpick inserted in center comes out clean, 30-35 minutes. Cool for 10 minutes; remove from pans to wire racks to cool completely.
  3. In a heavy saucepan, melt chocolate with cream over low heat. Remove from the heat; stir in vanilla. Transfer to a large mixing bowl; chill until slightly thickened, stirring occasionally. Beat on medium speed until light and fluffy. Chill until mixture achieves spreading consistency.
  4. For ganache, in a heavy saucepan, melt chocolate and butter. Gradually add cream; heat until just warmed. Chill until slightly thickened mixture achieves spreading consistency.
  5. Using a long serrated knife, cut each cake horizontally in half. Place 1 cake layer on a serving plate. Pipe a circle of filling around top edge of layer; spread one-third of the filling inside frosting. Repeat twice. Top with remaining cake layer. Spread ganache over top and sides of cake.

Nutrition Facts

1 piece: 723 calories, 52g fat (32g saturated fat), 118mg cholesterol, 282mg sodium, 60g carbohydrate (40g sugars, 4g fiber), 8g protein.

Here's to that chocolate fix we all need! I use cream in both the filling and glaze of this beautiful dessert. —Kathy Kittell, Lenexa, Kansas
Recipe Creator

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