Drain mandarin oranges well on a sieve. Cream the fat, 150 g sugar, vanillin sugar and half of the grated lemon peel. Stir in 3 eggs individually, alternating with 50 g flour.
Mix 200 g flour and baking powder and finally stir in briefly. Spread the dough on a greased, flour-dusted pan of the oven and sprinkle with the mandarins. For the cheesecake mixture, separate 7 eggs, put 3 egg whites in an extra bowl and chill.
Mix quark, 175 g sugar, 7 egg yolks, pudding powder and remaining lemon zest. Beat 4 egg whites until stiff and finally add 25 g sugar. Fold the beaten egg whites into the quark mixture, spread on the mandarins and smooth it down.
Bake in the preheated oven (electric cooker: 175 °C/ convection oven: not suitable/ gas: level 2) for approx. 25 minutes. Beat the remaining 3 egg whites until stiff and finally add 150 g sugar little by little.
Stir in lemon juice and spread the meringue as a blob on the cheese mixture. Bake for another 10-15 minutes. Let the cake cool down in the fat pan on a gridiron.