Triple Chocolate Mousse Cake - Vegetarian/Vegan

A very decadent dessert that even vegans can enjoy

Save
Triple Chocolate Mousse Cake - Vegetarian/Vegan Save
Triple Chocolate Mousse Cake - Vegetarian/Vegan

Step-by-step

  • Adjust oven rack to middle position and preheat oven to 325 degrees. Butter bottom and sides of 9 1/2 inch springform pan that is at least 3 inches high. Melt butter, chocolate, and espresso powder in large heatproof bowl set over saucepan filled with 1 inch of barely simmering water, stirring occasionally until smooth. Remove from heat and cool mixture slightly, about 5 minutes. Whisk in vanilla and egg yolks; set aside.
  • In stand mixer fitted with whisk attachment, beat room temp. egg whites and salt at medium speed until frothy, about 30 seconds. Add half of brown sugar and beat until combined, about 15 seconds. Add remaining brown sugar and beat at high speed until soft peaks form when whisk is lifted, about 1 minute, scraping down sides of bowl halfway through. Using whisk, fold one-third of beaten egg whites into chocolate mixture to lighten. Using rubber spatula, fold in remaining egg whites until no white streaks remain. Carefully transfer batter to prepared springform pan, gently smoothing top with offset spatula.
  • Bake until cake has risen, is firm around edges, and center has just set but is still soft (center of cake will spring back after pressing gently with finger) 13-18 minutes. Transfer cake to wire rack to cool completely, about 1 hour. Cake will collapse as it cools. Do not remove cake from pan.
  • Combine cocoa powder and water in small bowl; set aside. Melt chocolate in large heatproof bowl set over saucepan filled with 1 inch of barely simmering water, stirring occasionally until smooth. Remove from heat and cool slightly, 2 to 5 minutes.
  • In clean bowl of stand mixer fitted with whisk attachment, whip cold cream, granulated sugar, and salt at medium speed until mixture begins to thicken, about 30 seconds. Increase speed to high and whip until soft peaks form when whisk is lifted.
  • Whisk cocoa powder mixture into melted chocolate until smooth. Using whisk, fold one-third of whipped cream into chocolate mixture to lighten. Using rubber spatula fold in remaining whipped cream until no white streaks remain. Spoon mousse into springform pan over cooled cake and gently tap pan on counter 3 times to remove any large air bubbles; gently smooth top with offset spatula. Wipe inside edge of pan with damp cloth to remove any drips. Refrigerate cake at least 15 minutes while preparing top layer.
  • In small bowl, sprinkle Agar Agar over water; let stand at least 5 minutes. Place white chocolate in medium bowl. Bring 1/2 cup cream to simmer in small saucepan over medium-high heat. Remove from heat; add Agar Agar mixture and stir until fully dissolved. Pour cream mixture over white chocolate and whisk until chocolate is melted and mixture is smooth, about 30 seconds. Cool to room temperature, stirring occasionally, 5 to 8 minutes (mixture will thicken slightly).
  • In clean bowl of stand mixer fitted with whisk attachment, whip remaining cup cold cream at medium speed until it begins to thicken, about 30 seconds. Increase speed to high and whip until soft peaks form when whisk is lifted. Using whisk, fold one-third of whipped cream into white chocolate mixture to lighten. Using rubber spatula, fold remaining whipped cream into white chocolate mixture until no white streaks remain. Spoon white chocolate mousse into pan over middle layer. Smooth top with offset spatula. Return cake to refrigerator and chill until set, at least 2 1/2 hours.
  • If using, garnish top of cake with chocolate curls or dust with cocoa. Run thin knife between cake and side of springform pan; remove side of pan. Run clean knife along outside of cake to smooth sides. Cut into slices and serve.

Dark bittersweet chocolate meets a yielding baked base and a brilliant white chocolate agar-set finish in a dessert defined by distinct textural contrasts. Achieving this architectural marvel requires precise thermal management, particularly when melting the bittersweet chocolate over a water bath maintained at a bare simmer—if the water boils vigorously, the chocolate will seize into a grainy, unusable mass due to stray steam droplets.

Because this dessert relies on multiple chilling phases, mapping your workflow in advance prevents kitchen bottlenecks. While the baked bottom layer cools on a wire rack for one full hour and naturally collapses into a dense foundation, you can prepare the middle mousse layer and wash your mixing bowls thoroughly. Cold dairy whips significantly faster when the whisk attachment and bowl are chilled in the refrigerator for fifteen minutes prior to use, ensuring stable soft peaks that fold gracefully into the tempered chocolate without deflating the air you incorporated.

Pairing such a rich, high-fat confection demands acidity and brightness to reset the palate between dense, velvety bites. Pour tall glasses of high-acidity red wines like a dry Lambrusco, or offer tart raspberry coulis and fresh blackberries alongside each slice to cut through the heavy cocoa notes. If you are adapting this recipe for vegan diets, ensure your chocolate blocks are genuinely dairy-free and substitute the eggs with a reliable commercial replacer that handles mechanical aeration, though whipping aquafaba works exceptionally well as a structural mimic for egg whites when beaten to stiff peaks with the brown sugar.