Sift the flour with the cocoa. Whip the egg whites to a stable foam, gradually adding the sugar.

Add the yolks to the whites one at a time, whipping with a mixer after each. Add the flour-cocoa mix and gently fold in with a spatula.

Line the bottom of the pan with a circle of parchment, pour in the batter, and bake in an oven preheated to 180°C for 20 minutes.

Let the finished sponge cool, remove from the pan, and split it into three thin layers - using thread or a long sharp knife.

Separate the eggs into yolks and whites. Whisk the yolks by hand with half the sugar; whip the whites with a mixer into a foam with the other half. At the start of whipping, add half a teaspoon of lemon juice to each mixture.

Add the mascarpone to the yolk mixture and whisk by hand until fluffy. Once the mixture is smooth, gently fold in the egg whites.

Spread black currant jam over the bottom layer and cover with the second layer.

Spread half the cream over the second layer. Cover with the third layer and spread the remaining cream on top.

Chill in the fridge for an hour, then cut into pieces.

Drizzle each piece with melted chocolate and sprinkle with chopped nuts. Enjoy!