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Dark Chocolate Mousse Cake Recipe

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★★★★★

4.9 from 101 reviews

This decadent Dark Chocolate Mousse Cake features layers of moist chocolate cake filled and covered with a rich, velvety chocolate mousse and finished with a smooth chocolate ganache. Perfect for chocolate lovers, this impressive dessert combines the deep flavors of cocoa with a creamy texture, making it a delightful treat for any special occasion.

Ingredients

Scale

Cake

  • 1 and 3/4 cups (219g) all-purpose flour (spooned & leveled)
  • 1 and 3/4 cups (350g) granulated sugar
  • 3/4 cup (64g) unsweetened natural cocoa powder
  • 2 teaspoons espresso powder (optional)
  • 2 teaspoons baking soda
  • 1 teaspoon baking powder
  • 1 teaspoon salt
  • 3/4 cup (180g) full-fat sour cream, room temperature
  • 1/2 cup (113g/120ml) vegetable oil
  • 2 large eggs, room temperature
  • 1/2 cup (120g/ml) buttermilk, room temperature
  • 2 teaspoons pure vanilla extract
  • 1/2 cup (120g/ml) hot water or black coffee
  • 1 cup (170g) semi-sweet mini chocolate chips tossed in 1 Tbsp flour (optional)

Chocolate Mousse

  • 1/2 cup (120g/ml) hot water
  • 1/4 cup (21g) unsweetened natural or Dutch-process cocoa powder
  • 8 ounces (226g) quality semi-sweet chocolate, finely chopped
  • 2 cups (480g/ml) heavy cream, cold
  • 2 Tablespoons confectioners’ sugar
  • 1/2 teaspoon pure vanilla extract

Chocolate Ganache

  • 8 ounces (226g) quality semi-sweet chocolate, finely chopped
  • 1 cup (240g/ml) heavy cream

Optional Garnish

  • Fresh berries and/or chocolate shavings

Instructions

  1. Preheat and Prepare Pans: Preheat your oven to 350°F (177°C). Grease four 8-inch or 9-inch cake pans and line each with parchment paper rounds, then grease the parchment paper. This ensures easy removal of the cake layers after baking.
  2. Mix Dry Ingredients: In a large bowl, whisk together the all-purpose flour, granulated sugar, cocoa powder, espresso powder (if using), baking soda, baking powder, and salt until well combined. Set aside.
  3. Mix Wet Ingredients: In another large bowl, using a handheld or stand mixer with a whisk attachment or a whisk, blend sour cream, vegetable oil, and eggs on medium-high speed until smooth and combined. Add buttermilk and vanilla extract, mixing until incorporated.
  4. Combine Batter: Gradually add the dry ingredients into the wet mixture, then pour in hot water or black coffee. Whisk or beat on low speed just until combined. Gently fold in mini chocolate chips tossed in flour if using. Divide batter evenly among prepared pans.
  5. Bake the Cakes: Bake for 19–23 minutes or until a toothpick inserted in the center comes out clean. Allow cakes to cool in the pans on a wire rack for 1 hour. Run a knife around the edges, remove cakes, peel off parchment, and cool completely on the rack. Cakes may sink slightly in the center as they cool, which is normal.
  6. Prepare Chocolate Mousse: In a small bowl, whisk hot water and cocoa powder until smooth. Melt chopped chocolate in a double boiler or microwave (20-second increments, stirring after each) until smooth. Pour cocoa mixture into melted chocolate, stirring until thick and glossy. In a large bowl, whip cold heavy cream, confectioners’ sugar, and vanilla extract on medium-high speed until medium peaks form (about 3 minutes). Fold chocolate mixture gently into whipped cream, being careful not to deflate it. Cover and refrigerate for at least 2 hours or up to 2 days.
  7. Level and Assemble Cake Layers: If needed, level the cooled cakes by slicing thin layers off the tops to create flat surfaces. Place the first cake layer on your stand or serving plate. Spread about 1.5 cups (200g) of chocolate mousse evenly over the top. Place the second layer upside down on top, spread mousse again, repeat with the third layer right side up. Top with the final cake layer. Use remaining mousse as a crumb coat on top and sides, smoothing with a bench scraper. Refrigerate for 1 to 4 hours to set.
  8. Make Chocolate Ganache: Place chopped chocolate in a heatproof bowl. Heat heavy cream in a small saucepan over medium heat just until it simmers gently (do not boil). Pour hot cream over chocolate and let sit for 2–3 minutes to soften. Stir slowly until smooth and glossy. Refrigerate ganache for 30 minutes to 1 hour until thickened.
  9. Finish the Cake: Pour or spoon the thickened ganache over the chilled cake, smoothing top and sides with an icing spatula. Garnish with fresh berries and/or chocolate shavings if desired. Serve immediately or chill uncovered for 4–6 hours. Cake can be served at room temperature or chilled.
  10. Storage: Cover leftover cake tightly and store in the refrigerator for up to 5 days.

Notes

  • Use unsweetened natural cocoa powder for the best flavor. Dutch-process cocoa can also be used but alters acidity and taste slightly.
  • Espresso powder enhances chocolate flavor but is optional.
  • Buttermilk adds moisture and tenderness; if unavailable, make a substitute by adding 1/2 tablespoon lemon juice or vinegar to 1/2 cup milk and letting it sit for 5 minutes.
  • Hot water or black coffee can be used to intensify the chocolate flavor in the cake batter.
  • Folding in floured mini chocolate chips prevents them from sinking to the bottom.
  • Medium peaks in whipped cream are when the cream holds shape but is still soft and not stiff.
  • Do not overmix the mousse to maintain lightness.
  • Use a bench scraper for smoothing cake sides to get a professional finish.
  • Ganache should not be overheated or microwaved to avoid burning chocolate; if needed, use gentle melting methods.

Keywords: dark chocolate mousse cake, chocolate cake, mousse cake, layered cake, chocolate dessert, rich chocolate cake

Find it online: https://tastewithamy.com/dark-chocolate-mousse-cake-recipe/