For the chocolate cream, chop the couverture. Bring 600 g of cream to the boil, remove from the heat and melt the chocolate coating in it. Pour into a clean, dry bowl and chill overnight. For the sponge cake, lightly roast hazelnuts in a pan without fat, take them out and let them cool down. Separate the eggs. Beat the egg white and 3 tablespoons of water until stiff. Sprinkle sugar and vanilla sugar into the mixture. Stir in the egg yolks one after the other.
Mix flour, starch, 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 the sponge cake mixture and smooth it down. Bake in the preheated oven (electric range: 175 °C/ convection oven: not suitable/ gas: level 2) on the 2 rack from below for approx. 30 minutes. Let it cool down. Cut the sponge cake base in half horizontally once. Place a cake ring or springform pan rim around the bottom base. Mix orange marmalade with liqueur. Spread on the bottom. Put half of the chocolate cream into a high mixing bowl. Whip with the whisks of the hand mixer until stiff, pouring in 1 sachet of cream setting agent. Stir rosehip jam until smooth, put 4 tablespoons aside for decoration. Pour the chocolate cream onto the base and spread. Pour the jam in blobs on top and pull it through with a fork so that streaks appear. Place a second cake base on top.
Spread on the bottom. Put half of the chocolate cream into a high mixing bowl. Whip with the whisks of the hand mixer until stiff, pouring in 1 sachet of cream setting agent. Stir rosehip jam until smooth, put 4 tablespoons aside for decoration. Pour the chocolate cream onto the base and spread. Pour the jam in blobs on top and pull it through with a fork so that streaks appear. Place a second cake base on top. Whip the rest of the chocolate cream in a tall beaker until stiff. Sprinkle in 1 packet of cream firming agent. Pour onto the base and spread loosely. Chill for about 2 hours. Remove the cake from the rim. Whip 150 g cream until stiff, spread on the edge. Spread the rest of the jam as a blob on the cake. Sprinkle the hazelnut leaves on the edge and surface.
Whip the rest of the chocolate cream in a tall beaker until stiff. Sprinkle in 1 packet of cream firming agent. Pour onto the base and spread loosely. Chill for about 2 hours. Remove the cake from the rim. Whip 150 g cream until stiff, spread on the edge. Spread the rest of the jam as a blob on the cake. Sprinkle the hazelnut leaves on the edge and surface.
waiting time approx. 15 hours