Knead the ingredients for the crumble together, chill for 1/2 hour.
Mix the egg yolks with the butter, quark, sugar, vanilla sugar, salt and lemon zest. Mix the semolina and pudding powder, sift over and stir in. Beat egg whites until stiff and fold in.
Sprinkle a greased dish (24 cm) with half of the crumble. Fold the strawberries into the quark mixture, fill them with the crumble and sprinkle with the remaining crumble. Bake in the oven preheated to 180 degrees for 45-50 minutes.