Triple Chocolate Mousse Cake

Ingredients:

Chocolate and coffee cake

• 125 ml of boiling water
• 60 g dark chocolate, chopped
• 60 g butter, cut into pieces
• 1 large egg at room temperature
• 100 g of sugar
• 1 tsp vanilla extract
• 160 g of premium flour
• 1 teaspoon baking powder
• 3/4 tsp baking soda
• 1/4 teaspoon salt
• 125 ml of hot strong coffee

Mousse

• 720 ml heavy whipping cream, divided
• 350 ml milk chocolate, chopped
• 3 large egg yolks at room temperature
• 100 g of sugar
• 80 ml of water

Chocolate glaze

• 125 ml of water
• 100 g of sugar
• 60 ml heavy whipping cream
• 60 g cocoa powder, sifted
• 1.5 tbsp. l. powdered gelatin

Preparation:

1. Preheat oven to 160°C. Grease two 20cm cake pans. Line the bottoms with parchment paper and lightly flour the sides, tapping off any excess.
2. Whisk the chocolate and butter in boiling water until melted but still retaining small grains.
3. Beat the egg, sugar, and vanilla until the mixture doubles in volume (about 2 minutes on high speed with a mixer), then fold into the chocolate mixture with a spatula.
   
   Sift the flour, baking powder, baking soda, and salt into the same bowl and mix. Then stir in the hot coffee (the batter will become thinner). Pour the batter evenly into the prepared pans.
4. Bake the chocolate-coffee cake layers for about 25 minutes, until a tester inserted into the center comes out clean. Cool the layers completely in the pans.
   
   
   Note
   
   Please note that this cake only requires 1 layer, but it may be easier to bake the layers according to the full recipe and freeze the second one for later use. petit fours recipe.
5. MoussePrepare a 22cm springform pan by lining the bottom with parchment paper (this will make it easier to remove the mousse cake from the pan, but don't forget to remove the parchment paper afterwards). Whip 360ml of heavy cream until medium peaks form and refrigerate.
6. Heat the remaining 360 ml of cream until just barely simmering, then pour it over the chopped chocolate. Let it sit for 1 minute, then stir gently.
7. Place the egg yolks in a bowl and beat on high speed for one minute. In a small saucepan, heat the sugar and water over high heat and bring to a boil (buttering the sides of the pan occasionally) until the temperature reaches 120°C (250°F) on a syrup thermometer. Begin beating the egg yolks on medium speed, then pour the hot syrup down the side of the bowl carefully to avoid splashing. Increase the mixer speed to high and beat until the mixture doubles in volume and cools to about 40°C (just above body temperature).
8. Measure the temperature of the chocolate; it should also be close to 40°C (104°F), and stir the melted chocolate into the beaten egg yolks. Cool for 15 minutes or to room temperature, then fold in the chilled whipped cream in two additions.
9. Pour half the mousse into a springform pan. Cut one of the cake layers in half horizontally and place it on top of the mousse, centering it. Pour the remaining mousse over the cake layer and carefully place the other half of the cake layer on top, pressing gently to coat the sides of the cake layer without pressing it down too much. Wrap the pan in plastic wrap and place in the freezer to set the mousse, at least 4 hours or overnight.
10. Prepare the glaze while the cake is setting.: Combine water, sugar, and cream in a medium saucepan and bring to a boil. Once boiling, whisk in the cocoa powder and simmer (reduce heat if necessary) for 4 minutes, stirring frequently (the consistency will not change). Remove from heat. Soak the gelatin in 60 ml of cold water, then stir it into the hot mixture until completely dissolved. Cool the glaze to room temperature, then refrigerate for at least 3 hours. Set aside half the glaze for next recipe for petit fours.
11. Assemble the cakeRemove the cake from the freezer and invert the pan onto a wire rack placed over a parchment-lined baking sheet. Using a hair dryer on the lowest heat setting, gently heat the pan, first on the sides, then on top, to release the cake.
    
    Warm the cooled glaze, whisking occasionally, until melted and smooth. Pour it over the cake, carefully spreading it with a spatula to evenly coat the top and sides. Refrigerate the cake for at least 30 minutes, then transfer it to a stand and refrigerate until ready to serve. The mousse cake can be stored in the refrigerator for 4 days..