Separate eggs, beat egg whites and 4 tablespoons of cold water until stiff, adding sugar and vanilla sugar. Beat the egg yolks one after the other. Mix flour and baking powder, sieve onto the egg mixture and carefully fold in together with the almonds. Line a baking tray (approx. 32 x 39 cm) with baking paper. Spread the mixture evenly over it. Bake in the preheated oven (electric cooker: 200 °C/ convection oven: 175 °C/ gas: level 3) for 10-12 minutes. Moisten a clean tea towel, place on the worktop and sprinkle with a little sugar.
Use a knife to remove the sponge cake from the edge and turn it over onto the tea towel. Peel off the baking paper, wrap the tea towel over the sponge cake edges and let the sponge cake cool down (approx. 30 minutes). Mix plum puree with cinnamon or gingerbread spice and spread approx. 3/4 on the cooled sponge cake, leaving a 2 cm wide edge on the long sides. Whip the cream until stiff, allowing the cream setting agent to trickle in. Spread the cream evenly on the sponge cake base, leaving a margin of approx. 2 cm on the long sides. Roll up the sponge cake base from the long sides using a tea towel. Place the sponge roll on a plate, cover with foil and chill for approx. 4 hours, preferably overnight. Coarsely chop the chocolate coating. Melt the couverture and coconut oil over a warm water bath. Knead marzipan and icing sugar. Dust a work surface thinly with icing sugar. Roll out the marzipan into a thin rectangle (approx. 32 x 45 cm). Place sponge rolls on the marzipan plate, spread thinly with the remaining plum puree and roll up in the marzipan. Moisten the edges and press down well.
Melt the couverture and coconut oil over a warm water bath. Knead marzipan and icing sugar. Dust a work surface thinly with icing sugar. Roll out the marzipan into a thin rectangle (approx. 32 x 45 cm). Place sponge rolls on the marzipan plate, spread thinly with the remaining plum puree and roll up in the marzipan. Moisten the edges and press down well. Cut off any excess marzipan (approx. 30 g for stars). Place the sponge roll on a piece of baking paper and cover evenly with the chocolate coating. Spread the rest of the chocolate coating (or any that may have run down) on a porcelain plate or baking tray, chill and let it set. Use a spatula to push the couverture into small rolls and carefully spread it on the still slightly moist sponge roll. Refrigerate the sponge roll again for about 1 hour. If necessary, knead marzipan remains, roll out thinly and cut out small stars. Decorate the sponge roll with marzipan stars and dust with cocoa. Cut the sponge roll into 16-18 slices or about 12 cake pieces
Place the sponge roll on a piece of baking paper and cover evenly with the chocolate coating. Spread the rest of the chocolate coating (or any that may have run down) on a porcelain plate or baking tray, chill and let it set. Use a spatula to push the couverture into small rolls and carefully spread it on the still slightly moist sponge roll. Refrigerate the sponge roll again for about 1 hour. If necessary, knead marzipan remains, roll out thinly and cut out small stars. Decorate the sponge roll with marzipan stars and dust with cocoa. Cut the sponge roll into 16-18 slices or about 12 cake pieces
On 18 pieces: