Cream the fat, lemon zest, 200 g sugar, vanillin sugar and salt with the whisks of the hand mixer. Stir in 4 eggs one after the other. Mix flour and baking powder, stir in. Put the dough into a greased springform pan (26 cm Ø), dust with flour
Clean, wash, halve and stone the plums. Stir curd cheese, cream cheese and 125 g sugar until smooth. Stir in 4 eggs one after the other. Stir in the pudding powder at the end
Spread half of the plums on the dough and add the curd mixture. Spread the rest of the plums on the quark mixture, with the cut surface facing upwards
Bake the cake in a preheated oven (electric cooker: 175 °C/ convection oven: 150 °C/ gas: see manufacturer) for about 1 hour. If necessary, cover with foil in between. Remove the cake from the edge of the tin and let it cool down on a cake rack. Dust the edge with icing sugar before serving