Knead 375 g flour, 1 egg, 1 pinch of salt, 200 g butter in pieces and 2 tablespoons of cold water until smooth. Cover and chill for about 30 minutes.
Rub off the crust of the rolls, put crumbs aside. Soak rolls in milk. Heat oil in a large pan (28 cm Ø). Fry the sausage snail for 2-3 minutes on each side. Take out and let cool down. Remove skewers. Clean, wash and cut leek into rings. Steam in hot frying fat in portions for 3-4 minutes. Seasoning, leave to cool
Peel and chop onion and garlic. Steam both in 1 tbsp. hot butter until translucent. Wash and chop the marjoram. Separate 1 egg. Mix well 1 egg white, 4 eggs, onion mixture, marjoram and soaked rolls, season. Mix 1/3 mass with leek
Grease the springform pan (28 cm Ø). Roll out half of the dough on a little flour round (28 cm Ø). Line the bottom of the mould with it, prick it more often. Sprinkle with crumbs. Roll out the rest of the dough into 3 strips (each approx. 7 x 25 cm). Press to the edge of the mould
Pour the leek mixture into the mould. Slide the sausage snail onto it with the help of a flat lid. Spread the bread roll mixture over it. Fold over the protruding dough. Spread with whisked egg yolk. Bake in the preheated oven (electric oven: 200 °C/circulating air: 175 °C/gas: level 3) for 50-60 minutes
Not every butcher has the sausage from the meter in stock, so order it in time. It depends on the diameter (note the size of your springform pan!). The best thing for the cake is fine Thüringer-Bratwurst