Triple Chocolate Mousse

Triple Chocolate Mousse is the ultimate show-stopping dessert for chocoholics, layering dark, milk and white chocolate over a feather-light cocoa sponge. Follow this step-by-step guide to master the silky textures, stunning mirror glaze and restaurant-quality finish—all from your own kitchen.

Ingredients:

• Cocoa Sponge Base
  • 3 large eggs, separated
  • 80 g granulated sugar, divided
  • 50 g all-purpose flour, sifted
  • 20 g unsweetened cocoa powder
  • 1 g fine sea salt (small pinch)
• Dark Chocolate Mousse
  • 120 g dark chocolate (70 %), finely chopped
  • 2 g powdered gelatin (≈ 1 tsp)
  • 15 ml cold water (for blooming)
  • 200 ml cold heavy cream
  • 1 tsp vanilla extract
• Milk Chocolate Mousse
  • 120 g milk chocolate, finely chopped
  • 2 g powdered gelatin
  • 15 ml cold water
  • 200 ml cold heavy cream
• White Chocolate Mousse
  • 120 g white chocolate, finely chopped
  • 2 g powdered gelatin
  • 15 ml cold water
  • 200 ml cold heavy cream
• Chocolate Mirror Glaze
  • 60 g unsweetened cocoa powder
  • 120 g granulated sugar
  • 100 ml water
  • 80 ml heavy cream
  • 4 g powdered gelatin
  • 30 ml cold water (for blooming)

Instructions:

1. Prepare the cocoa sponge (15 min bake, 10 min prep)
   Preheat the oven to 180 °C / 355 °F and line a 20 cm / 8 in springform pan with baking paper. In a grease-free bowl, whisk the egg whites with the salt to soft peaks, sprinkle in 40 g of the sugar and whip to firm peaks. In a second bowl, beat the yolks with the remaining 40 g sugar until thick, pale and ribbon-like, about 3 minutes. Sift the flour and cocoa together over the yolk mixture and fold gently. Add one-third of the meringue to loosen, then fold in the rest just until no streaks remain. Spread the batter evenly in the pan and bake 12–15 minutes, until the centre springs back when touched. Cool completely, release the ring, then clamp a clean acetate collar or parchment strip inside the pan around the sponge.
2. Make the dark chocolate mousse
   Sprinkle gelatin over 15 ml cold water; stand 5 minutes to bloom. Gently melt the dark chocolate over a bain-marie or in 20-second microwave bursts; keep warm (32–35 °C). Whip 200 ml cold cream with the vanilla to very soft peaks. Microwave the bloomed gelatin 5 seconds to liquefy, stir into the warm chocolate, then immediately fold in one-third of the whipped cream to lighten. Fold in the remaining cream until silky. Pour the mousse over the sponge, level the surface, and refrigerate 20 minutes to partially set.
3. Make the milk chocolate mousse
   Repeat the blooming process with 2 g gelatin and 15 ml water. Melt the milk chocolate; stir in the melted gelatin. Whip 200 ml cream to very soft peaks and fold into the chocolate mixture in two additions. Spoon the mousse over the dark-chocolate layer, smooth carefully to avoid air pockets, and chill another 20 minutes.
4. Make the white chocolate mousse
   Bloom 2 g gelatin in 15 ml water. Melt the white chocolate, stir in the warmed gelatin and let cool to 30 °C so it doesn’t melt the lower layers. Whip the final 200 ml cream to very soft peaks, fold into the white chocolate, and pour over the cake. Level, cover and refrigerate at least 3 hours (or overnight) until completely set.
5. Prepare the chocolate mirror glaze
   Bloom 4 g gelatin in 30 ml cold water. In a small saucepan whisk cocoa powder, sugar and 100 ml water until lump-free. Bring to a gentle boil over medium heat and simmer 2 minutes, whisking. Remove from heat, stir in the heavy cream, then the softened gelatin until fully dissolved. Strain through a fine sieve into a jug. Cool, stirring occasionally, to 32 °C / 90 °F—the perfect pouring temperature for a flawless finish.
6. Glaze and finish the Triple Chocolate Mousse cake
   Place the fully chilled mousse cake on a wire rack set over a tray. Peel off the acetate collar in one smooth motion. Starting in the centre, pour the mirror glaze in a steady stream, allowing it to flow to the edges and coat the sides in a single pass. Avoid touching once glazed. Let the glaze drip and set for 5 minutes, trim excess from the base with a palette knife, and transfer the cake to a serving platter. Chill 30 minutes before slicing with a hot, dry knife for picture-perfect layers.

Triple Chocolate Mousse FAQ:

Q: Can I make Triple Chocolate Mousse in advance?
A: Yes—assemble the cake (up to the white chocolate layer) up to two days ahead, cover well and refrigerate. Prepare and pour the mirror glaze on the day you plan to serve for the freshest shine.

Q: How do I prevent the mousses from collapsing into each other?
A: Chill each mousse layer for at least 20 minutes (or until lightly set) before adding the next. Working with chocolate below 35 °C and cream whipped to very soft peaks also helps maintain distinct, even layers.

Q: Can I freeze leftover slices?
A: Absolutely. Freeze un-glazed layers tightly wrapped for up to one month. Thaw overnight in the fridge, then glaze and serve. Glazed slices can also be frozen, but the mirror finish may lose some shine on thawing.

Conclusion:

With its three silky layers and dazzling glaze, this Triple Chocolate Mousse cake turns any occasion into a celebration. Master the technique once and you’ll have an elegant dessert in your repertoire forever.

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