Wash strawberries, blueberries and currants. Clean the strawberries and cut them into halves or quarters depending on their size. Sort raspberries and blueberries. Strip currants from the stalks.
Marinate the fruit with 2 tablespoons of sugar and lemon juice. Whip the cream with the whisks of the hand mixer until stiff. Mix quark, vanilla sugar and 5 tablespoons of sugar. Fold in cream and chocolate crumble.
Arrange the quark with fruit in a bowl.