Separate eggs. Beat the egg whites, 2 tablespoons of water and 1 pinch of salt with the whisk of the hand mixer until stiff, adding 100 g sugar and vanilla sugar. Stir in the egg yolks one after the other. Mix flour, 20 g cocoa and baking powder and fold in
Put the sponge cake into a greased, flour-spread box form (approx. 25 cm long; 1.5 litres capacity), spread it out smoothly. Bake in a preheated oven (electric cooker: 175 °C/ convection oven: 150 °C/ gas: stage 2) for 20-25 minutes, remove from oven, let cool on a cake rack for about 15 minutes
Turn out the sponge cake from the mould and let it cool down for about 2 hours. In the meantime defrost the raspberries. Soak gelatine in cold water. Mix mascarpone, quark and 50 g sugar. Whip cream until stiff
Squeeze the gelatine, dissolve, stir in 2-3 tbsp. mascarpone quark mixture, stir into the remaining mixture. Fold in cream. Set aside 200 g cream cream. Fold raspberries into the rest of the cream
Cut the sponge cake into three horizontal thirds. Sprinkle each base with 1 tablespoon of grappa. Spread half of the cream on the lower cake base, cover with the next cake base. Spread the rest of the cream on top, cover with the last cake base
Pour the cream set aside into a piping bag with a large perforated spout (approx. 1 cm Ø) and spray onto the cake in a wavy pattern. Chill the cake for at least 1 hour. Dust with cocoa, cut into approx. 10 pieces
waiting time approx. 3 1/4 hours