Mix the flour, 1/8 litre lukewarm water, egg yolk, salt and 2 tablespoons of oil with the dough hooks of the hand mixer for approx. 8 minutes to a smooth dough. Knead the dough on the work surface with your hands and rub with oil. Wrap in cling film and let rest for about 1 hour. In the meantime clean, wash and stone the sour cherries. Squeeze the curd with a clean tea towel in portions (approx. 200 ml liquid). Melt butter.
Remove the crusts from the toast and crumble. Beat eggs and sugar until frothy. Fold in quark, pudding powder and 100 g poppy seed baking. Roll out strudel dough thinly on a floured cloth (50x70 cm). With floured hands pull out evenly over the back of your hands in a wafer-thin layer (40x60 cm). Spread the dough with butter and sprinkle with crumbs. Leave a 3 cm wide rim all around. Spread the quark and poppy seed mixture on the bottom 2/3 of the dough. Sprinkle with cherries and the remaining poppy seeds. Roll up the strudel with the help of the cloth from underneath. Wrap the sides and place diagonally on a baking tray lined with baking paper. Bake in the preheated oven (electric cooker: 200 °C/ convection oven: 175 °C/ gas: level 3) for 40-50 minutes.
Leave a 3 cm wide rim all around. Spread the quark and poppy seed mixture on the bottom 2/3 of the dough. Sprinkle with cherries and the remaining poppy seeds. Roll up the strudel with the help of the cloth from underneath. Wrap the sides and place diagonally on a baking tray lined with baking paper. Bake in the preheated oven (electric cooker: 200 °C/ convection oven: 175 °C/ gas: level 3) for 40-50 minutes. Serve the strudel lukewarm. Whipped cream tastes good with it