Cut the chocolate into small pieces. Process 200 g butter, 125 g sugar, 250 g flour and almonds into crumble with the dough hook of the hand mixer. Stir in 100 g chocolate, chill.
Carefully wash, clean and drain the currants. Mix 250 g butter, 150 g sugar, vanilla sugar and salt until creamy. Stir in eggs one at a time. Mix 375 g flour and baking powder. Briefly stir in alternately with sour cream.
Stir in the rest of the chocolate. Spread the dough on the greased drip pan (32 x 40 cm) of the oven. Spread the berries on top. Cover with sprinkles.
Bake in a preheated oven (electric stove: 175 °, fan oven: 150 °, gas level 2) for about 30 minutes. Let cool, cut into pieces and serve fresh.