Peel and cook the potatoes. Let the boiled potatoes cool down and mash them. Squeeze the quark well in a cloth or drain well in a sieve.
Beat the butter, sugar and eggs into a frothy mixture. Stir in lemon zest and quark. Now add the flour, potatoes and sultanas and mix everything into a smooth dough. Shape the dough into small cubs and fry them in the margarine in a pan on both sides until golden brown. Serve warm with cinnamon sugar.
A fruit compote or applesauce also goes well with it. The amount is enough as a dessert for about 4 people. As a sweet main course, it is enough for about 2 people.