Separate eggs. Beat the egg whites and 3 tablespoons of water until stiff, adding 100 g of sugar. Stir in egg yolk and cappuccino powder. Mix flour, starch and baking powder and fold in. Line a baking tray with baking paper and spread the mixture evenly on top. Bake in the preheated oven (electric cooker: 200 °C/ convection oven: 175 °C/ gas: level 3) for approx. 8 minutes.
Turn the sponge cake onto a tea towel sprinkled with sugar, remove the paper and roll it up with the towel from the long side. Soak gelatine in cold water. Wash the cherries, dab dry, stone and chop coarsely. Put the chopped cherries on a piece of kitchen paper and dab dry. Put the apricots in a sieve, drain and puree. Mix yoghurt, apricot puree and 80 g sugar. Squeeze out the gelatine and dissolve lukewarm. Stir in 3 tablespoons of cream, then stir into the remaining cream. Chill the cream for about 20 minutes until it starts to gel. Whip cream until stiff and fold in. Finally, fold in the cherries. Carefully roll out the sponge roll and spread with the cream.
Stir in 3 tablespoons of cream, then stir into the remaining cream. Chill the cream for about 20 minutes until it starts to gel. Whip cream until stiff and fold in. Finally, fold in the cherries. Carefully roll out the sponge roll and spread with the cream. Roll up the sponge cake again and let it freeze for at least 5 hours. Cut roll into 15 pieces with a hot knife. Sprinkle the pieces with sugar and cut a small notch in the pieces for the wafer