For the dough:
- Knead a shortcrust pastry from butter, sugar, egg, baking powder and flour. Line the bottom and edge of a springform pan with it.
- Bring the butter, milk and sugar to the boil and let cool down a little. Mix the quark, vanilla sugar, custard powder and eggs together. Stir in the butter-milk-sugar mixture.
- Spread the whole thing on the dough. Slide into the tube. Caution liquid!
- Bake at 180 ° for 50-60 minutes.