Separate eggs. Beat the egg whites with 3 tablespoons of cold water and salt until stiff with the whisk of the hand mixer, finally adding 60 g sugar and 1 packet of vanilla sugar. Add egg yolks one after the other and fold in. Mix flour and baking powder, sieve onto the egg foam and fold in. Line a baking tray (approx. 34 x 41 cm) with baking paper. Spread the mixture evenly on the baking tray. Bake in the preheated oven (electric cooker: 200 °C/ convection oven: 175 °C/ gas: see manufacturer) for approx. 8 minutes.
Lightly moisten a tea towel and sprinkle with sugar. Remove the baking tray from the oven, remove the sponge cake from the edge and turn it over onto the tea towel. Carefully peel off the baking paper, place the edges of the tea towel over the sponge cake and let it cool down
Soak gelatine in cold water. Whip 100 g cream until stiff and chill. Mix quark, 25 g sugar and lemon peel. Squeeze the gelatine, dissolve over low heat and mix with 1 tbsp. quark cream. Stir the gelatine mixture into the remaining quark cream and chill for about 10 minutes. Spread the sponge cake with 250 g raspberry fruit spread, except for an approx. 2 cm wide rim. When the quark cream starts to gel, stir again briefly and fold in the whipped cream. Spread the quark cream on the sponge cake, except for an approx. 2 cm wide rim, and roll it up from a short side. Put the sponge roll in a cool place for about 2 hours
Raspberries selected. The remaining berries are also selected, carefully washed and drained well. Clean the strawberries and cut them into pieces. Pluck the currants from the panicles. Mix lemon juice, remaining fruit spread and 40 g sugar and mix with the berries.
Whip 200 g cream and 1 packet of vanilla sugar until stiff. Cut the sponge roll into 8-9 thick slices (3.5-4 cm each) and place on a plate with the cut surface facing down. Spread pieces all around with cream and lift onto a cake plate. Spread the berries on the tartlets shortly before serving
waiting time approx. 2 3/4 hours