For the dough, beat the fat, 300 g sugar, vanillin sugar and salt with the whisk of the hand mixer until foamy. Gradually fold in the eggs. Mix flour and baking powder, sieve onto the fat egg mass, add lemon zest and stir in. Pour the dough into a greased, breadcrumbed pan of the oven. Smooth and bake in the preheated oven (electric: 175 °C/ gas: level 2) for 20-25 minutes.
Remove from the oven, place on a rack and allow to cool. In the meantime, wash the grapes, pluck them from the panicles and drain them well in a sieve. Then spread on the cooled base. Mix the cake glaze and the remaining sugar in a saucepan, stir carefully with apple juice and 250 ml water with a stirring spoon. Bring to the boil while stirring constantly. Then distribute evenly over the grapes from the middle. Put the cake in a cool place for about 1 1/2 hours. Dust with icing sugar and serve decorated as desired with lemon balm. Whipped cream tastes good with it.
Bring to the boil while stirring constantly. Then distribute evenly over the grapes from the middle. Put the cake in a cool place for about 1 1/2 hours. Dust with icing sugar and serve decorated as desired with lemon balm. Whipped cream tastes good with it. Makes about 20 pieces