Chocolate Mousse Layer Cake
Indulge in this ultra-rich chocolate mousse layer cake featuring dark and milk chocolate mousse sandwiched between soft chocolate cake, perfect for any occasion!
Servings 8 servings
Calories 450kcal
Ingredients
For the Cake
- 1.5 cups all-purpose flour Stick with regular flour for a soft, tender crumb
- 1 cup granulated sugar White sugar gives the perfect sweetness
- 0.5 cup unsweetened cocoa powder Dutch-processed or natural—choose your favorite rich cocoa
- 1.5 tsp baking powder
- 0.5 tsp baking soda Makes your cake rise light and lofty
- 0.5 tsp salt Emphasizes chocolate flavors
- 2 large eggs Best at room temperature for a smoother batter
- 0.5 cup vegetable oil Keeps your cake moist for days
- 1 cup buttermilk Use regular milk with a squeeze of lemon juice if needed
- 1 tsp vanilla extract Brings out the dreamy chocolate notes
For the Mousse
- 200 g dark chocolate, chopped Choose at least 60% cocoa for depth
- 200 g milk chocolate, chopped For creamy, sweet mousse contrast
- 500 ml heavy cream, divided Be sure it’s cold so it whips up stiff
- 3 tbsp powdered sugar Sweetens and stabilizes the whipped cream
- 2 tsp gelatin powder For a stable mousse texture
- 3 tbsp water To bloom the gelatin
For the Ganache
- 200 g dark chocolate, chopped
- 200 ml heavy cream For the glossy ganache topper
Garnish
- Chocolate shavings or chunks Optional but highly recommended for garnish
Instructions
Prep & Bake the Cake
- Preheat your oven to 350°F (175°C). Grease and line a 9-inch round cake pan.
- In a big bowl, whisk flour, sugar, cocoa, baking powder, baking soda, and salt.
- In another bowl, whisk eggs, oil, buttermilk, and vanilla. Combine, mix until smooth (don’t over-mix!).
- Pour into your pan and bake for 25–30 minutes. Cool completely.
Make the Chocolate Mousses
- Melt the dark and milk chocolate separately and allow to cool slightly.
- Sprinkle gelatin over water; let it stand for 5 minutes, then heat gently to dissolve.
- Whip 400 ml heavy cream with powdered sugar to soft peaks. Split in half.
- Stir dissolved gelatin into dark chocolate, then fold in half the whipped cream. Repeat with milk chocolate.
- Chill both mousses for 15 minutes to set up slightly.
Assemble the Cake
- Slice cooled cake in half horizontally. Place the bottom layer in a springform pan.
- Smooth dark chocolate mousse over the bottom cake layer. Add the second cake layer and top with milk chocolate mousse.
- Smooth the top and refrigerate at least 4 hours (overnight is best).
Finish with Ganache
- Warm 200 ml cream until just bubbling. Pour over chopped dark chocolate, let sit 1 minute, then stir until silky.
- Cool until slightly thickened, then pour over the chilled cake.
Slice & Enjoy
- For picture-perfect slices, run a knife under hot water and wipe between cuts.
Notes
For best results, use room temperature ingredients, and ensure to properly chill the cake to keep layers intact. The quality of chocolate truly impacts the flavor of your mousse cake.
