Separate eggs. Beat the egg whites and 3 tablespoons of cold water with the whisks of the hand mixer until stiff. Add 75 g sugar and salt. Stir in egg yolks. Mix flour, baking powder and starch, sieve in portions onto the egg mixture and fold in carefully. Pour the mixture onto a baking tray (32 x 39 cm) lined with baking paper and smooth it down. Bake in the preheated oven (electric cooker: 200 °C/ convection oven: 175 °C/ gas: level 3) for about 10 minutes.
Turn out onto a tea towel sprinkled with sugar. Carefully remove the baking paper. Immediately roll up tightly with the cloth from the long side. Allow to cool. Soak gelatine in cold water. Rinse lemon thoroughly with hot water, finely grate peel. Cut the lemon in half and squeeze out the juice (yields approx. 75 ml). Mix quark, lemon peel and juice, 100 g sugar and vanillin sugar. Squeeze out the gelatine, dissolve and stir in 2 tbsp. quark. Then stir into the remaining quark mixture. Chill for 4-8 minutes until the mixture begins to gel. Whip cream until stiff and fold into the gelling quark mixture.
Mix quark, lemon peel and juice, 100 g sugar and vanillin sugar. Squeeze out the gelatine, dissolve and stir in 2 tbsp. quark. Then stir into the remaining quark mixture. Chill for 4-8 minutes until the mixture begins to gel. Whip cream until stiff and fold into the gelling quark mixture. Roll out the sponge cake. Spread the quark mixture evenly and leave a 2 cm wide edge on one long side (the side to which you roll up). Leave about 1 cm of edge on the narrow sides. Leave the cream on the sponge cake plate for another 8 minutes. Roll up from the long side. Chill for about 3 hours. Dust with icing sugar, cut into pieces and serve
Roll out the sponge cake. Spread the quark mixture evenly and leave a 2 cm wide edge on one long side (the side to which you roll up). Leave about 1 cm of edge on the narrow sides. Leave the cream on the sponge cake plate for another 8 minutes. Roll up from the long side. Chill for about 3 hours. Dust with icing sugar, cut into pieces and serve
waiting time approx. 3 1/4 hours