For the currant and curd cake, beat the butter until fluffy, add the powdered sugar and vanilla sugar and continue to beat until creamy. Gradually beat in the eggs. Fold in the flour and stir in the milk.
Spread the dough on a baking tray lined with baking paper. For the topping, separate the 2 eggs. Mix curd cheese with yolks and powdered sugar. Beat the egg whites with a pinch of salt until stiff and fold into the curd mixture.
Spread the curd mixture on the dough and sprinkle with the currants. Bake the currant curd cake in a preheated oven at 180 °C for approx. 40 minutes.