Preheat oven to 175 °C. Roll out the dough with a dough roller and form a circle of about 30 cm. Then place the dough on a buttered cake tin or one covered with baking paper and pre-bake for 10 minutes.
ATTENTION: To prevent the dough from bloating, place some weight on the dough. You can use uncooked beans or rice. Personally, I simply place baking paper over the dough and put a plate on top. It always works quite well!
Stir the low-fat quark and the yoghurt together. Mix sugar, jam sugar, vanilla sugar, lime zest and starch and stir in. Separate the 3 eggs.
Mix the egg yolks individually in the cheese mixture. Beat the egg whites with salt until stiff and fold in.
Pour the cheese mixture onto the short pastry. Place the blueberries on top and press them lightly into the cheese mixture.
Bake the cake for 50 minutes at 175 °C. Allow the cake to cool slightly before cutting and serving.