Defrost the raspberries, about 15 of them with the tips pointing upwards, place them on a piece of kitchen paper and set aside. Separate the eggs. Beat egg white and 3 tbsp. water until stiff. Add sugar and vanilla sugar. Fold in egg yolks one after the other. Mix flour, ground nuts and baking powder and fold into the egg cream
Line the bottom of a springform pan (26 cm Ø) with baking paper. Fill in sponge cake mixture and smooth it down. Bake in the preheated oven (electric cooker: 175 °C/ convection oven: 150 °C/ gas: level 2) for 15-20 minutes. Let it cool down on a cake rack
Soak gelatine in cold water. Puree raspberries with icing sugar and raspberry brandy and pass through a sieve. Squeeze the gelatine well and dissolve over a warm water bath. Stir some of the puree into the gelatine and then stir into the rest of the puree. Whip 200 g cream until stiff and fold in
Remove the base from the pan and remove the baking paper. Cut the base in half horizontally. Place a cake ring around the lower cake base. Pour cream on it, smooth it down, place the upper cake layer on top. Chill for at least 4 hours.
Chop the chocolate and melt over a warm water bath. Roast nut flakes in a pan without fat, remove and let them cool down
Whip 400 g cream until stiff. Fill about half into a piping bag with a large perforated spout. Spread the cake with the rest of the cream. Pull a cake comb along the edge of the cake from bottom to top. Spray tuffs onto the cake. Fill chocolate into a piping bag and cut off a small tip. Draw lines over the edge of the cake and tuffs. Just before serving, decorate with the raspberries and hazelnut leaves set aside