Home Recipes Cake Triple Chocolate Mousse Cake: The Ultimate Showstopper Dessert

Triple Chocolate Mousse Cake: The Ultimate Showstopper Dessert

Name: Triple Chocolate Mousse Cake
Prep time: 90 min
Cook time: 20 min
Total time: 600 min
Ingredients: ¼ cup 56g unsalted butter, room temp; ½ cup 104g granulated sugar; ¼ cup 58g sour cream, room temp; ½ tsp vanilla extract; 2 large egg whites (room temp); ½ cup + 2 tbsp (81g all purpose flour); ¼ cup + 2 tbsp (43g dark cocoa powder); 1 ⅛ tsp baking powder; ¼ tsp salt; ¼ cup 60ml milk, room temp; 2 tbsp water (room temp); 6 oz 170g semi sweet chocolate chips; 2 tbsp 30ml light corn syrup; ½ tsp vanilla extract; ½ cup 120ml heavy whipping cream; 4 large egg yolks; ¼ cup 52g granulated sugar; 1 ¾ cups 420ml heavy whipping cream, divided; 8 oz 227g semi sweet chocolate chips; ¾ cup 86g powdered sugar; 1 ¼ tsp unflavored gelatin; 1 ½ tbsp 23ml cold water; 9 oz 255g white chocolate chips; 1 ¾ cups 420ml heavy whipping cream, cold, divided; ⅓ cup 38g powdered sugar

Rebecca Hopkins

July 1, 2020

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What if you could combine a rich, dark chocolate cake, a layer of glossy chocolate fudge, a cloud of silky chocolate mousse, and a crown of smooth white chocolate mousse into one stunning dessert? That is the magic of this Triple Chocolate Mousse Cake. It’s not just a cake; it’s an elegant, layered experience that is guaranteed to impress everyone who sees and tastes it.

While this dessert looks like it came from the finest patisserie, the magic is that it’s built from four distinct, manageable components. Each layer is a celebration of chocolate in a different form, creating a symphony of textures from fudgy to airy light. It’s the perfect project for a special occasion, a holiday centerpiece, or when you want to create something truly unforgettable. Let’s build something spectacular!

Why You’ll Love This Triple Chocolate Mousse Cake

An Unforgettable Showstopper: The elegant, clean layers make this cake the undisputed star of any dessert table. It’s as beautiful as it is delicious.
A Textural Dream: Experience four distinct layers: a tender cake base, a firm fudge, a creamy chocolate mousse, and a light white chocolate mousse. Every bite is an adventure.
Perfect for Making Ahead: This cake needs time to set, which makes it ideal for preparing a day (or even two) before your event. No last minute baking stress!
Chocolate Lover’s Paradise: With dark cocoa, semi sweet chocolate, and white chocolate, this cake satisfies every possible chocolate craving in one elegant package.
A Rewarding Baking Project: While it has multiple steps, each component is straightforward. It’s the perfect recipe to showcase your skills and patience.

Building the Ultimate Triple Chocolate Mousse Cake

This recipe is a project best approached in stages. Read through the entire recipe first, and remember that chilling time is a crucial ingredient!

Part 1: The Dark Chocolate Cake & Fudge Layer

Cake Ingredients:

¼ cup (56g) unsalted butter, room temperature
½ cup (104g) granulated sugar
¼ cup (58g) sour cream, room temperature
½ tsp vanilla extract
2 large egg whites, room temperature
½ cup + 2 tbsp (81g) all purpose flour
¼ cup + 2 tbsp (43g) dark cocoa powder (like Hershey’s Special Dark)
1 ⅛ tsp baking powder
¼ tsp salt
¼ cup (60ml) whole milk, room temperature
2 tbsp water, room temperature

Fudge Layer Ingredients:

6 oz (170g) semi sweet chocolate chips
2 tbsp (30ml) light corn syrup
½ tsp vanilla extract
½ cup (120ml) heavy whipping cream

Instructions:

1Bake the Cake: Preheat oven to 350°F (176°C). Grease an 8 inch round cake pan and line the bottom with parchment. Cream butter and sugar until light and fluffy (3-4 mins). Beat in sour cream and vanilla. Add egg whites one at a time. Whisk dry ingredients in a separate bowl. Combine milk and water. Alternately add dry ingredients and milk mixture to the batter, beginning and ending with dry ingredients. Spread into pan and bake for 19-21 minutes, until a toothpick comes out with a few crumbs. Cool completely.

2Assemble the Base: Line an 8×3 inch springform pan with a parchment paper collar that extends 2 inches above the rim. (A cake collar or a regular pan lined with plastic wrap also works). Level the cooled cake if needed and place it in the bottom of the prepared pan.

3Make the Fudge Layer: Place chocolate chips, corn syrup, and vanilla in a bowl. Heat cream until simmering, then pour over chocolate. Cover and let sit 5 minutes, then whisk until smooth. Pour over the cake layer, spread evenly, and refrigerate for 1 hour to set.

Part 2: The Chocolate Mousse Layer

Ingredients:

4 large egg yolks
¼ cup (52g) granulated sugar
1 ¾ cups (420ml) heavy whipping cream, divided
8 oz (227g) semi sweet chocolate chips
¾ cup (86g) powdered sugar

Instructions:

1Cook the Custard: In a heatproof bowl set over a pot of simmering water (double boiler), whisk egg yolks, ¼ cup sugar, and ½ cup of the heavy cream. Cook, whisking constantly, until thickened, pale, and reaches 160°F (71°C), about 7-10 minutes. Remove from heat.

2Melt Chocolate & Combine: Melt the chocolate chips. Vigorously whisk the warm custard into the melted chocolate until smooth. Let cool to room temperature.

3Fold in Whipped Cream: Whip the remaining 1 ¼ cups of heavy cream with the powdered sugar to stiff peaks. Fold about a quarter of the whipped cream into the chocolate mixture to lighten it, then gently fold the chocolate mixture into the remaining whipped cream until no streaks remain.

4Add the Layer: Spread the chocolate mousse evenly over the set fudge layer. Refrigerate for 1 hour.

Part 3: The White Chocolate Mousse Layer

Ingredients:

1 ¼ tsp unflavored powdered gelatin
1 ½ tbsp (23ml) cold water
9 oz (255g) white chocolate chips
1 ¾ cups (420ml) heavy whipping cream, cold, divided
⅓ cup (38g) powdered sugar

Instructions:

1Bloom Gelatin: Sprinkle gelatin over water in a small dish. Let sit 5 minutes.

2Melt White Chocolate: Place white chocolate chips in a bowl. Heat ½ cup of the cream until simmering. Add the bloomed gelatin and whisk until dissolved. Pour hot cream over white chocolate, let sit 3-5 minutes, then whisk until smooth. Cool to room temp.

3Fold in Whipped Cream: Whip the remaining 1 ¼ cups of cold cream with powdered sugar to stiff peaks. Gently fold the cooled white chocolate mixture into the whipped cream in three additions.

4Final Layer: Spread the white chocolate mousse evenly over the chocolate mousse layer. Refrigerate the entire cake for at least 4-6 hours, preferably overnight, until completely firm.

To Finish:

Carefully remove the springform pan and parchment collar. Smooth the sides with an offset spatula if needed. Garnish with chocolate curls and a dusting of cocoa powder. Keep refrigerated until serving.

Pro Tips for Success

Room Temperature is Key: For the cake, ensure butter, sour cream, egg whites, and milk are at room temperature for proper emulsification and rise.
Don’t Rush the Cooling: Let each chocolate mixture (fudge, mousse bases) cool to room temperature before folding in whipped cream or proceeding to the next layer. If they are too warm, they will deflate the air you whipped in.
Gentle Folding: Use a spatula and fold gently to maintain the mousse’s airy texture. Over mixing will make it dense.
The Right Pan: An 8×3 inch springform pan is highly recommended. The tall sides and removable ring make assembly and serving effortless.
Patience is a Virtue: This cake’s structure depends on proper setting time. Rushing the chill will result in messy slices.

This Triple Chocolate Mousse Cake is a labor of love that yields incredible rewards. I hope it brings as much joy to make as it does to share and enjoy.