Black Tie Mousse Cake

Step 1

Preheat oven to 350˚F. Lightly grease a 9-inch springform pan with cooking spray. Set aside.

Step 2

Sift together the sugar, flour, cocoa, baking powder, baking soda, and salt into a large bowl.

Step 3

Add the egg, milk, oil, and vanilla. Stir until incorporated. Heat 1/4 cup of water in a glass measuring cup in the microwave until boiling (30-60 seconds). Pour boiling water into batter and mix until fully incorporated. The texture of the batter should be consistent throughout. Batter will be thin, but shouldn't have watery spots. Pour batter into the prepared pan.

Step 4

Bake chocolate cake at 350˚F for 15-18 minutes, or until a toothpick comes out clean or with a few moist crumbs when inserted in the center of the cake. Remove from oven and place the pan in the freezer to chill the cake.

Step 5

VANILLA CREAM CHEESE: Place the cream cheese, powdered sugar, salt, and vanilla in a large bowl. Beat together with an electric hand mixer until smooth. Set aside. (No need to clean the beaters. Use them for the next step.)

Step 6

CHOCOLATE CREAM CHEESE: Place the cream cheese in a large bowl. Sift the powdered sugar and cocoa powder over the top of the cream cheese. Add the salt and vanilla. Beat together with an electric hand mixer until smooth. Set aside. (Now clean the beaters for a future step.)

Step 7

STABILIZED WHIPPED CREAM: In a small microwaveable bowl, stir together the unflavored gelatin and cold water. Set aside for 5 minutes to absorb and solidify.

Step 8

Place cold heavy cream in the bowl of a stand mixer. Using the whisk attachment, beat until mixture is thickened, but not quite soft peaks.

Step 9

Nuke gelatin in microwave for 10 seconds to melt it. Stir until smooth and no longer foggy/grainy; mixture will start to look more transparent/clear. Slowly drizzle the liquid gelatin into the cream while the mixer is running on low speed. (It’s important to do this slowly to avoid lumps.)

Step 10

Slowly increase speed to medium-high and whip until stiff peaks form. (Just until it starts to look thick and leaves trails from the whisk. Do not over-mix or it will curdle and turn into butter. Keep a close eye on it.)

Step 11

Divide the stabilized whipped cream, placing half in the vanilla cream cheese mixture and half in the chocolate cream cheese mixture. Use the electric hand mixer to beat the vanilla mixture first. Then the chocolate. No need to clean the beaters in-between.

Step 12

Spread the chocolate mousse mixture evenly over the frozen chocolate cake. Then dollop the vanilla mousse over the top of the chocolate mousse and carefully spread even. Cover the pan with plastic wrap (try not to let it touch the top) and chill in the fridge for a minimum of 1 hour.

Step 13

After the mousse has set, carefully remove the edge of the springform pan, but keep the cake on the base and place it back in the fridge.

Step 14

Place the semi-sweet and white chocolate chips into two separate bowls. In a small saucepan on LOW, heat heavy cream and butter until it just comes to a boil. Stir the mixture to make sure the butter is completely melted.

Step 15

Measure 2 Tbsp of the cream/butter mixture and put it on top of the white chocolate chips. Pour the remaining butter/cream mixture over the semi-sweet chocolate chips. Let the cream melt the chocolate chips and then stir them up in their separate bowls. Let the ganaches cool slightly until spreading consistency. Set aside 1/2 cup of the semi-sweet chocolate ganache, and place the white chocolate ganache in a piping bag, but wait to cut the tip.

Step 16

Place a cooling rack inside of a cookie sheet and set the cake on top of the cooling rack. (The ganache that falls off the cake will be caught in the cookie sheet underneath the cooling rack.) Pour the semi-sweet chocolate ganache over the top of the cake; spread evenly with an offset spatula. When the chocolate drips over the edges, smooth the ganache with your spatula.

Step 17

Once the cake is coated, cut the tip of the bag of white chocolate ganache and pipe horizontal stripes on top of the cake about 1-inch or so apart. Immediately use a toothpick to gently drag lines through the ganache across the full cake in vertical motions, alternating going up and down across the cake. (*See photo tutorial in post.)

Step 18

Quickly press the mini chocolate chips onto the side of the cake while the ganache is still wet. Place the semi-sweet ganache that was set aside into a piping bag fitted with a coupler and Wilton 21 open star piping tip. Pipe a border around the edge. I piped a reverse shell pattern.

Step 19

Once fully decorated, store the cake in the fridge until the ganache has set completely, at least 15-20 minutes or more, as desired.

Step 20

When ready to serve, cut cake with a hot, dry knife. Rinsing the knife in hot water and drying the knife between cuts for crisp slices.