Whenever I think of a fancy flavoring for a cake, I immediately go to kir royale. Mostly because of Patisserie Chantilly in Lomita, where they do a kir royale mousse. With this classic French cocktail, you have the rich fruity notes of black currant against the light, tart notes of the champagne. It is a simple but effective combination! I have made kir royale cakes in the past, but this one is more of a full-on cake, as opposed to just mini entremets or petit gateau. For the cake itself, I went with a rather straightforward vanilla sponge cake as the base, soaking it with actual kir royale just to get that flavor in there. I enrobed the cake in a kir royale mousse, made by taking kir royale, reducing it into a syrup, mixing that with white chocolate to stabilize it, and then finishing it with some heavy cream to lighten the whole affair up. The topping was where I had a ton of fun, since I had black currant powder. I have always wanted to do a cake with fun piping on top, where you then do a dusting of something that coats portions of said piped topping. The end result is a fun, changes-with-perspective contrast on the top of the cake, though admittedly, the cake kind of reminds me of radicchio. This cake was a lot of fun to make, came together quite quickly all in all, and is a part of the continuous homage to a dessert that inspired me all those years ago.

For the sponge cake:
2 eggs, separated
1/4 cup granulated sugar
2 tbsp canola oil
1/3 cup all-purpose flour
a pinch of salt
1 tsp vanilla extract
Whip the egg whites with the sugar to stiff peaks. Whip the egg yolks with canola oil first. Then first into the yolks your flour and salt. Then add in the vanilla. Fold the egg whites through the egg yolk-flour mixture to form your batter. Spread the batter onto a lined quarter sheet tray. Bake at 350 degrees F for 18 minutes. Cut out a 5-inch round of the cake, and freeze the cake so that it is firm to the touch.

For the kir royale soak:
1 tbsp black currant concentrate
1 tbsp champagne
a pinch of salt

Mix together to form your soak.

For the kir royale mousse:
3oz black currant concentrate
3oz champagne
2 tsp gelatin powder + 2 tbsp cold water
1/4 cup white chocolate
a pinch of salt
6oz heavy cream, whipped stiff

In a pot, heat up the black currant concentrate, champagne, and gelatin until everything is dissolved together, and reduce by half. Stir in the white chocolate and salt, and let that all melt down into the liquid as well. Pass through a sieve and allow the mixture to cool down to room temperature before folding the heavy cream into it.

For initial assembly:
Brush the cake with the soak. Line a 6-inch ring mold with cling wrap and cooking spray, and place onto a parchment or silpat-lined sheet tray. Pour the mousse into the ring mold first, then press the cake round into it. Freeze the cake for at least 3 hours before attempting to unmold.

For the mascarpone topping:
4oz mascarpone cheese
a pinch of salt
1/4 tsp vanilla extract

Stir everything together until combined. Transfer to a piping bag with a star piping tip.

For garnish:
Freeze-dried black currant powder

Pipe the mascarpone on top of the mousse cake. Dust the top with the black currant powder to finish.