Bottom Layer:
90g Unsalted butter
7oz Bittersweet Chocolate
3/4 tsp Instant Espresso powder
4 large eggs ~ separated
1-1/2 tsp Vanilla extract
1/8 tsp Salt
1/3 cup Light brown sugar
Directions:
- Preheat oven to 160 deg C. Combine butter, chocolate & espresso in a large heatproof bowl set over a pan of barely simmering water. Stir occasionally until melted & smooth. Remove from heat & allow to cool slightly (abt 5 mins). Whisk in egg yolks & vanilla & set aside.
- Using a stand mixer whip egg whites & salt on medium-low speed until foamy. Add half sugar & continue whipping until combined & add remaining sugar, increase speed to high & whip until soft peaks form.
- Fold 1/3 egg whites into the chocolate mixture to lighten & fold in remaining egg whites till no white streaks remain. Carefully transfer batter to 9" spring-form pan. Smooth top with spatula & bake cake for 13-18 mins. Transfer to a wire rack to cool completely, about 1 hour. Do not remove the cake from pan.
Middle Layer:
5 tbsp hot water
2 tbsp cocoa powder
7oz bittersweet chocolate
1-1/2 cups heavy cream ~ chilled
1 tbsp granulated sugar
1/8 tsp salt
Directions:
- Combine hot water & cocoa in a small bowl & set aside. Place chocolate in a large heatproof bowl set over a pan of barely simmering water. Stir occasionally until melted & smooth. Remove from heat & allow to cool slightly (2-5 mins)
- Using a chilled stand mixer fitted with a chilled whisk attachment, whip cream, sugar & salt on medium-low speed until foamy. Increase speed to high & whip until soft peaks form. Whisk cocoa mixture into chocolate.
- Using a hand whisk, fold 1/3 of the cream into the chocolate mixture to lighten. Fold in remaining cream till no white streaks remain, spoon mousse onto cooled cake. Smooth top with a spatula & gently tap on counter to release any air bubbles. Wipe inside the edge of the pan with a damp cloth or paper towel to remove any drips. Refrigerate for at least 15 mins while preparing the top layer.
Top Layer:
3/4 tsp powdered gelatin
1 tbsp water
6oz white chocolate chips
1-1/2 cup heavy cream ~ chilled
Shaved chocolate or cocoa powder for decorating (Optional)
Directions:
- Sprinkle gelatin over water & let sit for at least 5 mins to bloom.
- Place white chocolate in a medium heatproof bowl, bring 1/2 cup of cream to a simmer in a small saucepan over medium-high heat. Remove from heat & stir in gelatin mixture until completely dissolved.
- Pour cream mixture over white chocolate, cover & allow to sit for 5 mins. Whisk gently until smooth. Let cool to room temperature, stirring occasionally.
- Using a chilled stand mixer fitted with the chilled whisk attachment, whip remaining cup of cream on medium-low speed until foamy. Increase speed to high & whip until soft peaks.
- Fold 1/3 of the cream into the white chocolate to lighten. Fold in remaining cream till no white streaks remain. Spoon white chocolate mousse into the pan over the middle layer. Smooth top with a rubber spatula. Return to refrigerator & chill until set, at least 2-1/2 hours. The cake can be refrigerated up to 1 day. Allow sitting at room temperature for about 45 mins before slicing.
- Serve, garnish the cake with chocolate curls, or dust with cocoa if desired. Run a thin knife between the cake & sides of the pan. Remove sides & run the cleaned knife along the outside to smooth. Cut using cheese wire or a hot knife, cleaning & drying between each cut.