Chocolate Coffee Mousse Cake Recipes

Steps:

• For the brownie: Preheat the oven to 350 degrees F. Spray the bottom of a 9-inch springform pan with nonstick cooking spray.
• Whisk together the flour, cocoa powder and sugar in a medium bowl. Whisk in the milk, butter, vanilla and egg until smooth. Pour the batter into the prepared pan and bake until a knife inserted in the center comes out clean, about 20 minutes. Cool completely on a wire rack, about 30 minutes.
• Unclasp the pan, remove the outer ring and spray it with nonstick cooking spray. Line the ring with a 2 1/2-inch-wide parchment strip, making sure that it sits tightly and smoothly along the sides. Re-clasp the ring to the bottom of the pan with the cake in it.
• For the mousse: Roughly chop 4 tablespoons of the butter and put in a medium microwave-safe bowl. Microwave in 30-second intervals, stirring in between each, until melted, about 1 minute. Stir in 1/4 cup of the cocoa powder until smooth; set aside. Chop the remaining 8 tablespoons butter and put in a medium microwave-safe bowl. Microwave in 30-second intervals, stirring in between each, until melted, about 1 minute. Stir in the remaining 1/2 cup cocoa powder until smooth; set aside.
• Add 1/4 cup of the heavy cream to a small microwave-safe bowl and stir in the gelatin. Let sit for 5 minutes to bloom. Microwave in 30-second intervals, stirring in between each, until the gelatin is dissolved, about 1 minute. Cool to room temperature, about 5 minutes.
• Transfer the gelatin to the bowl of a stand mixer fitted with the whisk attachment and add the sugar, vanilla and remaining 3 3/4 cups heavy cream. Whisk on medium speed until stiff peaks form, 3 to 4 minutes. Divide the whipped cream mixture between 2 large bowls. Fold one bowl of the cocoa powder-butter mixture into each batch of whipped cream mixture and stir until no streaks remain (one bowl will contain dark chocolate mousse and the other will contain light chocolate mousse).
• Spread the dark chocolate mousse on top of the brownie in the springform pan. Use an offset spatula to even out and smooth the top. Spread the light chocolate mousse on top of the dark chocolate mousse and use an offset spatula to even out and smooth the top. Refrigerate until the mousse is set, 3 hours and up to overnight.
• For the ganache: Bring the heavy cream and butter to a boil in a small saucepan over medium-high heat. Put the semisweet chocolate in a large heatproof bowl and pour the hot cream over top. Let it sit for 5 minutes, then stir until smooth and shiny.
• Unclasp the springform pan and remove the parchment paper from the sides of the cake. Use a hot, dry offset spatula to smooth out the sides. Set a rack in a rimmed baking sheet and put the cake on top of the rack. Pour the ganache over the cake and let it drip down over the sides so the entire cake is covered. Swipe once across the top with a clean, large offset spatula to create a smooth top. Refrigerate until set, about 30 minutes.
• Hold a stencil or other tool with holes (such as a doily or a cooling rack) over the cake (do not lay it on the ganache; it will stick) and dust with more cocoa powder to create a decorative pattern. Serve immediately.

Steps:

• Make the cake: Prepare the cake mix as the label directs for a 9-by-13-inch cake. Bake; cool slightly in the pan, then invert onto a rack to cool completely.
• Clean out the cake pan and line it with plastic wrap. Cut the cake in half lengthwise, then in thirds crosswise to make 6 rectangles. Using a serrated knife, slice each rectangle in half to make two layers. Arrange half of the pieces snugly in the cake pan. Crumble the remaining pieces and press tightly into 6 small balls; arrange 1 cake ball in the center of each cake rectangle in the pan.
• Make the mousse: Heat the chocolate, butter, coffee and 1/4 cup water in a heatproof bowl set over a saucepan of simmering water (do not let the bowl touch the water), stirring, until melted. Remove the bowl from the pan; stir until cool. Reserve the simmering water. Fill a large bowl with ice water.
• Whisk the egg yolks, 1 1/2 cups sugar and 2 tablespoons water in a separate large heatproof bowl. Set the bowl over the saucepan of simmering water and whisk until pale yellow, 6 to 8 minutes. Add the chocolate-coffee mixture and the vanilla and whisk until combined, about 2 minutes. Remove the bowl from the pan and set in the bowl of ice water; whisk until slightly cool but not thick, about 4 minutes.
• Beat the egg whites and salt in a bowl with a mixer until foamy. Add 2 tablespoons sugar and beat until almost stiff; gently fold into the chocolate-yolk mixture to make a dark chocolate mousse. Spread 5 cups over the cake and cake balls. Freeze until firm on top, about 30 minutes.
• Beat the heavy cream and the remaining 4 tablespoons sugar until soft peaks form; fold into the remaining mousse. Remove the cake from the freezer; spread with the light chocolate mousse, cover with plastic wrap and freeze until firm, at least 6 hours or overnight.
• Make the chocolate shell: Stir the chocolate, heavy cream and 4 tablespoons corn syrup in a heatproof bowl set over a saucepan of simmering water (do not let the bowl touch the water) until melted. A spoonful at a time, spread half of the shell mixture over the frozen mousse. Return to the freezer.
• Make the chocolate sauce: Add the remaining 1 tablespoon corn syrup and the butter to the remaining chocolate shell mixture. Microwave 30 seconds, then stir until glossy.
• To serve the cake, beat the heavy cream with a mixer until foamy. Add the sugar and beat until soft peaks form. Remove the cake from the freezer; invert onto a baking sheet and unmold, then invert again onto a platter, chocolate shell-side up.
• Cut the cake in half lengthwise using a warm knife, then cut into thirds crosswise to make 6 rectangles; cut each rectangle in half diagonally to make 2 triangles. Top each triangle with whipped cream, ice cream and the prepared chocolate sauce.