Mix flour, 75 g sugar, salt and baking powder. Add 1 egg, 150 g quark, milk and oil, knead to a smooth dough with the dough hooks of the hand mixer. Divide the dough into 12 equal parts. Form into circles (approx. 12 cm Ø) with floured hands and press flat. Place 4 flat cakes on a baking tray lined with baking paper. Mix sour cream, 250 g quark, 2 eggs, sauce powder and 75 g sugar with the whisk of the hand mixer.
Spread evenly on the 12 flat cakes. Sprinkle blueberries over them. Bake the trays one after the other in a preheated oven (electric cooker: 175 °C/ convection oven: 150 °C/ gas: level 2) for 20-25 minutes. Remove, place on a grid and dust the edges with icing sugar. Decorate with lemon balm. Yoghurt tastes good with it