Put flour, 100 g sugar, salt, 1 egg and 200 g butter in small pieces in a mixing bowl and knead with the dough hooks of the hand mixer. Finally, knead the mixture with your hands, wrap in foil and chill for about 30 minutes. In the meantime, wash the oranges hot, rub dry and finely grate the zest of 2 oranges. Mix 150 g butter and 150 g sugar in a large bowl until creamy. Stir in 5 eggs one after the other. Add quark, sour cream, pudding powder and orange zest to the butter-sugar mixture and mix everything to a smooth cream. Roll out the cooled shortcrust pastry evenly on a greased or greaseproof pan of the oven (32 x 38 cm) lined with baking paper.
Prick the base several times with a fork. Spread the curd cream on the base and smooth it down evenly. Bake in the preheated oven (electric cooker: 175 °C/ convection oven: 150 °C/ gas: level 2) for approx. 45 minutes. In the meantime peel the remaining oranges so that the white skin is completely removed. Cut oranges into slices. After 20 minutes baking time, place the slices on the cake and continue baking. Serve the cake decorated with candied orange slices and peel
Waiting time approx. 20 minutes