Wash, clean and drain 250 g strawberries and cut them in half or quarters depending on size. Grease the bottom of a springform pan (26 cm Ø) and sprinkle with breadcrumbs.
Separate eggs. Mix egg yolks, butter, sugar, salt and vanilla sugar in a large mixing bowl with the whisk of the hand mixer for 3-5 minutes until light creamy. Mix pudding powder, starch and baking powder.
Alternately stir in quark and lemon juice.
Beat the egg white until stiff and fold into the dough in portions. Carefully fold in prepared strawberries. Pour the quark mixture into the springform pan, smooth it down and bake in a preheated oven (electric cooker: 175 °C/ convection oven: 150 °C/ gas: see
manufacturer) about 1 hour 5 minutes bake.
Stir the jam until smooth. Spread the cake evenly about 15 minutes before the end of the baking time, cover with foil and bake until done. Turn off the oven and let the cake rest in the oven for about 30 minutes.
Remove from the oven, remove foil and let the cake cool down on a cake rack.
Wash and clean 500 g strawberries, drain well and cut in half. Remove the cake from the tin. Spread strawberries on top and dust with icing sugar if necessary.