Melt the butter and add the milk. Remove from the heat and dissolve the yeast in the warm milk mixture. Add sugar, eggs, salt and cardamom and whisk together. Add flour gradually and knead the dough thoroughly. Let the dough rise covered until doubled in size, about 1.5 hours. Turn the dough down and roll it out in about 2 cm thickness. Then cut out 10 small circles.
Remove the cheese from the refrigerator. Heat oil in a pan (or frying pan) and fry the berliners until golden – it takes about 2 - 4 minutes. Let them drain on a paper towel and then roll in sugar.
Cut the cheese into small pieces and serve with Berliners and jam.