Line a baking tray (approx. 35 x 40 cm) with baking paper. Separate the eggs. Beat the egg whites, 6 tbsp. cold water and 1 pinch of salt until stiff. Add 150 g sugar and 1 packet of vanilla sugar.
Beat the egg yolks separately. Mix all the flour, starch and baking powder, sieve onto the egg mass and fold in. Spread on the baking tray. Bake in the preheated oven (electric cooker: 200 °C/circulating air: 175 °C/gas: level 3) for approx. 12 minutes.
Sprinkle a moist, well expressed (important so that the sponge cake will come off well later!) tea towel with 3 tablespoons of sugar. Turn the sponge cake onto the tea towel, remove the baking paper immediately.
Let the sponge cake cool down for about 30 minutes.
Whip 500 g cream until stiff, while pouring in 2 packets of vanilla sugar. Spread 500 g cranberries on the sponge cake. Spread with the cream. Cut the sponge cake into 5 long strips.
Roll up the sponge cake strips spirally to form a cake (like a liquorice snail). Whip 250 g cream until stiff, pour in 1 sachet of vanilla sugar. Spread loosely on the cake. Dust the edge of the cake with icing sugar.
Put 2 tablespoons of cranberries as a blob on the cake.