For the shortcrust pastry, knead all ingredients with the dough hooks of the hand mixer to a smooth dough. Cover and let it rest in the fridge for about 30 minutes. Grind the poppy seeds finely. Put them into a pot with sugar, fat and milk and let it boil up once.
Remove from the stove and let it swell for about 30 minutes. For the quark mixture, stir the fat and sugar until foamy. Add the eggs one after the other. Fold in quark, pudding powder, lemon peel and lemon juice. Drain the cherries.
Grease a springform pan (26 cm Ø) and press the short pastry into it. Pull up an approx. 4 cm high rim. First spread the poppy seed mixture on the base. Spread the cherries on top and cover with the quark mixture.
Smooth out and bake in a preheated oven (electric: 175 °C/ gas: level 2) for about 1 hour. Remove from the springform pan and let cool. Dust with icing sugar.