Cream fat, salt, 250 g sugar and vanillin sugar with the whisk of the hand mixer. Stir in the eggs one after the other. Mix flour and baking powder, sieve onto the fat egg mass and stir in. Spread the dough evenly on a greased and breadcrumbed baking tray (32x38 cm). Bake in the preheated oven (electric cooker: 175 °C/ convection oven: 150 °C/ gas: level 2) for approx. 30 minutes. Remove from the oven and let it cool down on a grid.
Turn the base onto a plate and fold it over with a frame. In the meantime, carve the vanilla pod and scrape out the pulp. Soak the gelatine in cold water. Bring milk, vanilla pod and pulp and 250 g sugar to the boil. Beat the egg yolks in a beating pot. Pour hot milk into the egg yolk while stirring vigorously. Stir over a hot water bath until the cream thickens. Stir in squeezed gelatine and stir cold over a water bath. Whip the cream until stiff. As soon as the mixture begins to set, fold in the cream. Spread the cream on the base and refrigerate for at least 6 hours, preferably overnight. Wash and clean the strawberries.
Stir in squeezed gelatine and stir cold over a water bath. Whip the cream until stiff. As soon as the mixture begins to set, fold in the cream. Spread the cream on the base and refrigerate for at least 6 hours, preferably overnight. Wash and clean the strawberries. Cut the cake into 24 pieces and decorate each piece with strawberries. Heat the jelly, let it cool down briefly and put it on the strawberries. Decorate with lemon balm as desired