Crumble the yeast. Sprinkle with 10 g of sugar, let stand for 2 minutes, then stir until smooth. Put 350g flour, yeast, 40g sugar, lukewarm milk, egg, 50g butter and a pinch of salt in a bowl. Knead into a smooth dough with the dough hook. Cover and let rise in a warm place for 30 minutes.
Streusel: First crumble 100g flour, 75g butter, brittle, cinnamon and 50g sugar with the dough hook, then with your hands to make crumbles.
Apple cream: Mix the sour cream, lemon zest, pudding powder and applesauce.
Apples: peel, quarter, core, cut into wedges. Mix with the lemon juice.
Knead the yeast dough again with your hands, roll out on a floured surface the size of a tray. Place on a greased tray and spread on the apple cream. Place the apple slices close together and spread the crumble over them.
Bake in the preheated oven at 200 ° C on the 2nd rack from the bottom for 40-45 minutes (convection: 180 ° C). Let cool and serve dusted with powdered sugar.