Wash the plums, drain well, halve and stone
Cream the fat, 200 g sugar, vanillin sugar, lemon zest and salt with the whisks of the hand mixer. Add 4 eggs one after the other, alternating with 1 tbsp. flour each, and mix well. Mix remaining flour (approx. 300 g) and baking powder and stir in briefly
Grease a fat pan of the oven (approx. 34 x 41 cm) and dust with flour. Spread the dough evenly in the fat pan. Spread the plums with the cut surface facing upwards and sprinkle with 1-2 tbsp. sugar. Bake in the preheated oven, middle shelf (electric oven: 175 °C/ convection oven: 150 °C/ gas: see manufacturer) for approx. 40 minutes
Mix sour cream, 2 eggs, sauce powder and 50 g sugar to a smooth glaze. After about 20 minutes, remove the cake from the oven and spread the icing on top. Put the cake back into the oven and bake in about 20 minutes. Remove the cake from the oven and let it cool down. Sprinkle with sugar crystals
waiting time approx. 2 hours