Turn the onions into the left bacon and let them cool.
Put the flour, crumbled yeast, lukewarm milk, salt and the egg in a bowl, mix, add butter and use the dough hook of the hand mixer to make a yeast dough that is not too light.
Shape or roll out the dough on a baking sheet. Let go.
Mix the cooled onions with the eggs and sour cream, season with salt and spread on the dough. Sprinkle a little caraway seeds on top.