Knead the flour, 175 g butter, 1 egg and 125 g sugar first with the dough hooks of the hand mixer, then with your hands to a smooth dough. Roll out dough thinly on the greased fat pan of the oven (32 x 39 cm). Refrigerate the tray for approx. 1 hour
Pre-bake on the middle rack in the preheated oven (electric oven: 175 °C/ convection oven: 150 °C/ gas: see manufacturer) for approx. 10 minutes. Meanwhile bring the jam to the boil and pass through a sieve. Wash lemon hot and rub dry. Rub half of the peel thinly. Halve the lemon and squeeze the juice. Mix 100 g butter and 200 g sugar with the whisk of the hand mixer until creamy. Gradually stir in quark, sour cream, vanilla sugar, semolina, lemon juice and zest. Stir in 6 eggs one after the other
Remove the fat pan from the oven. Pour half of the quark mixture onto the shortcrust pastry. Spread half of the jam generously on the cream with a spoon and swirl. Repeat the process with the rest of the cream and jam. Bake on the lower rack at the same temperature for 40-50 minutes. Remove from the oven and let cool on a cake rack
Waiting time approx. 1 hour