Warm the milk lukewarm. Melt the fat in it. Mix 50 ml milk-fat mixture and yeast. Mix 25 g sugar, salt and flour in a bowl and make a depression in the middle. Pour yeast milk into the middle and mix with some flour from the rim. Cover with flour and leave to rise for about 15 minutes until the surface gets cracked
Add the remaining milk and 1 egg and knead to a smooth dough. Cover the dough and let it rise in a warm place for about 45 minutes
Wash and quarter the plums and remove stones. Cut plums into slices. Mix quark, vanillin sugar, 75 g sugar, 5 eggs and sauce powder
Roll out the yeast dough rectangularly (slightly larger than 1/2 baking tray; approx. 33 x 21 cm) on a floured work surface. Grease a good half of the baking tray, dust with flour and cut in half with folded aluminium foil. Lay out the dough on the greased half. Spread plum wedges on the dough and pour over. Bake the cake in a preheated oven (electric cooker: 200 °C/ convection oven: 175 °C/ gas: see manufacturer) for 30-40 minutes. Cover the surface for the last 10 minutes with aluminium foil if necessary
Take the cake out of the oven and let it cool down. Cut the cake into pieces and serve
Waiting time approx. 45 minutes