Triple Chocolate Mousse Cake

 

Ingredients

For the bottom layer:

• 6 tablespoons unsalted butter
• 7 oz bittersweet chocolate, chopped
• ¾ teaspoon instant espresso powder
• 4 large eggs, separated
• a pinch of salt
• ⅓ cup packed brown sugar
• 1½ teaspoons vanilla extract

For the middle layer:

• 2 tablespoons unsweetened cocoa powder
• 5 tablespoons hot water
• 7 oz bittersweet chocolate, chopped
• 1½ cups heavy cream
• 1 tablespoon granulated sugar
• ⅛ teaspoon salt

For the top layer:

• 1 tablespoon water
• ¾ teaspoon powdered gelatin
• 6 oz white chocolate, chopped
• 1½ cups heavy cream, divided

Instructions

first, make the bottom layer
Preheat the oven to 325ºf and spray a springform pan with cooking spray.
Put the butter, chocolate, and espresso powder in a large microwave-safe bowl. Microwave in 30-second intervals, stirring for at least 10 seconds between each, until everything is melted and smooth (or melt it in a double boiler). Set aside.
Meanwhile, in the bowl of a stand mixer fitted with the whisk attachment, beat the egg whites and salt at medium speed until the eggs are frothy. Add the brown sugar and increase the speed to high. Keep beating until soft peaks form.
Add the vanilla and egg yolks to the chocolate mixture and stir to combine. Add about ⅓ of the egg white mixture to the bowl, and gently fold in using a wooden spoon or rubber spatula. Add the rest of the egg whites and fold everything together (still gently) until it is uniform in color.
Pour the batter into the prepared springform pan and smooth the top. Bake it for 15-18 minutes, until it is just barely set. Let the cake cool completely in the pan.
then, make the middle layer
In a small bowl, dissolve the cocoa powder into the hot water and set aside.
Put the chocolate in a large microwave-safe bowl. Microwave it in 30-second intervals, stirring for at least 10 seconds between each, until it is completely melted.
In the bowl of a stand mixer fitted with the whisk attachment, add the cream, sugar, and salt. Beat the mixture on high speed until soft peaks form.
Stir the cocoa powder mixture into the melted chocolate and mix until it is smooth. Add about ⅓ of the whipped cream and gently fold in using a wooden spoon or rubber spatula. Gently fold in the rest of the whipped cream until everything is uniform in color. Spread the mousse on top of the cooled cake in the springform pan, and put it in the fridge to chill while you make the top layer.
then, make the top layer
Put the water in a small bowl and sprinkle the gelatin over the top. Let it sit for 5 minutes until the gelatin is softened.
Put the white chocolate in a medium bowl and set aside.
Put ½ cup of the cream into a small saucepan. Heat it over medium heat until small bubbles start to form, remove it from the heat, and stir in the gelatin mixture until it is completely dissolved. Pour it over the white chocolate and stir it until the chocolate is completely melted and smooth.
Add the rest of the heavy cream to the bowl of a stand mixer fitted with the whisk attachment. Beat it on high speed until soft peaks form. Gently fold ⅓ of the whipped cream into the chocolate mixture using a wooden spoon or rubber spatula. Then fold in the rest of the whipped cream until everything is uniform in color. Spread the mixture evenly over the mousse that is already in the springform pan.

Let the whole cake chill in the fridge for at least 2½ hours.