Dumpling with Meat Filling
Scrub potatoes and cook 1/3 of them in a pot of boiling salted water until knife-tender, about 20 minutes. Drain and rinse in cold water, then drain again.
Soak the day-old roll in milk. Rinse, clean and dice the leek. Heat the butter in a pan and saute the leek. Add the ground meat and saute until brown and crumbly. Remove from the heat and let cool slightly. Squeeze the bread of excess milk and add to the ground meat mixture. Add the egg and sausage and knead into a moldable mixture. Season with salt and pepper. Shape into 8 small meatballs, cover and refrigerate.
Peel the remaining potatoes, grate finely and squeeze out the excess water with the help of a kitchen towel. Reserve the juice and let sit until the starch has settled. Drain the water and the starch to the grated potatoes. Peel the cooked potatoes and press through a ricer into the raw potatoes. Add the egg yolks. Season with salt and nutmeg. Mix well into a smooth dough. If the dough is wet add potato starch as needed. Remove a dumpling-sized amount, flatten in your plam and place a meatball in the center. Surround the meatball with the dough forming a dumpling. Continue with the remaining dough and meatballs.
Cook the dumplings together in boiling salted water, reduce the heat and simmer for about 25 minutes. Serve immediately.