Knead 400 g flour, baking powder, 100 g sugar, 1 vanillin sugar, 1 pinch of salt, 200 g butter in pieces and 2 eggs first with a hand mixer, then briefly with your hands until smooth. Cover and chill for about 30 minutes.
For the choux pastry, boil 3/8 l water, 100 g butter and 1 pinch of salt. Add 200 g flour at once. Stir with a wooden spoon until the dough comes off the bottom of the pot as a lump and a white film forms there. Remove from the heat. Immediately knead in 1 egg with the hand mixer. Cool down for about 10 minutes. Knead in another 1 egg. Cool down for about 20 minutes.
Drain the cherries. Grease a fat pan (approx. 32 x 39 cm; at least 3.5 cm deep) and dust with flour. Dust the shortcrust pastry with a little flour, roll out on the fat pan and press up the edge by about 2 cm. Prick the base several times with a fork
Mix quark, 5 eggs, 250 g sugar, 2 vanillin sugar and lemon peel. Stir 3 portions into the choux pastry (the choux pastry spreads like granules). Fold in cherries and chocolate drops. Spread loosely on the short pastry. Bake in the preheated oven (electric cooker: 175 °C/circulating air: 150 °C/gas: level 2) for approx. 1 1/4 hours. Cool down on the fat pan