Knead the flour, 50 g sugar, salt, 1 egg and butter in small pieces first with the dough hooks of the hand mixer, then with your hands to a smooth dough. Cover and chill for about 30 minutes. Grease a tart mould (24 cm Ø) with lift-off base. Roll out the dough round (approx. 28 cm Ø) on a work surface dusted with flour. Line the mould with it, press it on, cut off any protruding edges. Prick the dough base several times with a fork
Sort, clean and wash the blueberries and drain well. Mix quark, buttermilk, 2 eggs, pudding powder and 75 g sugar until smooth. Stir the blueberries into the icing and spread on the base. Bake in the preheated oven (electric cooker: 175 °C/ convection oven: 150 °C/ gas: level 2) for approx. 40 minutes. Remove the tart from the oven, let it cool down for about 15 minutes, lift the base out of the mould. Let the tart cool down on a cake rack and arrange on a plate
Waiting time approx. 30 minutes