Cream fat, 100 g sugar, vanillin sugar and salt with the whisk of the hand mixer. Separate the eggs. Put the egg white in a cool place. Add egg yolk to the fat-sugar-mixture and stir until creamy.
Mix flour and baking powder. Stir in half. Knead in the remaining flour with the dough hooks. Put the dough in a cool place for about 20 minutes. In the meantime wash the currants, drain well and remove from the panicles.
Roll out the dough into a circle (34-35 cm Ø) on a floured work surface. Line a greased springform pan (26 cm Ø) with it (the edge of the springform pan should be 4-4.5 cm high). Prick the bottom several times with a fork.
Place the mould in a cool place for another 10 minutes. Carefully mix currants and starch. Beat the egg whites until stiff and finally add the remaining sugar. Fold the egg whites into the currants in portions.
Pour into the tin, smooth out a little and bake in the preheated oven (electric: 175 °C/ gas: level 2) for 65-70 minutes. If necessary, cover the cake 20 minutes before the end of the baking time. Remove the cake from the oven and let it cool down on a grid in the mould.
Remove the cooled cake from the mould and serve decorated with lemon balm as desired. Makes about 12 pieces.