Beat the eggs, 100 g sugar, vanillin sugar and salt in a hot water bath until the sugar is dissolved. Continue beating cold until a thick, firm cream is formed. Mix flour and starch, sieve onto the egg mixture and fold in. Spread the sponge mixture on a baking tray lined with baking paper. Bake in the preheated oven (electric range: 225 °C/ convection oven: not suitable/ gas: level 4) for 8-10 minutes on the 2nd rack from below. Take out and turn over onto a damp tea towel.
Moisten baking paper with a little water and remove. Cover the sponge cake with a 2nd damp tea towel and let it cool down. In the meantime soak gelatine in cold water for about 5 minutes. Bring lime juice and zest, white wine and 150 g sugar to the boil. Squeeze out the gelatine well, dissolve it in the water and chill for approx. 45 minutes. In the meantime, wash the strawberries, drain and pat dry. Clean and halve the strawberries. Whip cream until stiff. As soon as the lime-wine mixture begins to gel, fold in the cream. Halve the sponge cake crosswise. Spread the sponge halves with the cream. Spread strawberries on top.
Whip cream until stiff. As soon as the lime-wine mixture begins to gel, fold in the cream. Halve the sponge cake crosswise. Spread the sponge halves with the cream. Spread strawberries on top. Roll up each half and chill for about 2 hours. Dust with icing sugar and cut open. Place each piece in 2 paper sleeves placed one inside the other and serve
waiting time approx. 2 hours