Soak rolls in cold water. Peel and finely dice 1 onion. Finely chop 1 teaspoon of capers. Knead the squeezed bread roll, minced meat, diced onion, chopped capers and egg.
Season to taste with salt, pepper and nutmeg. Shape them into medium-sized dumplings. Bring the stock to the boil. Let the dumplings simmer for 15-20 minutes at medium heat. In the meantime, clean and wash the mushrooms for the sauce and cut them into fine slices.
Peel the remaining onion and chop finely. Heat the fat, fry the mushrooms and onion for about 5 minutes, turning them over. Season with salt and pepper. Dust with flour. Add cream and 600 ml broth while stirring and bring to the boil.
Season with salt, pepper, capers and lemon juice. Serve the dumplings in the sauce. Serve garnished with parsley. Serve with parsley potatoes, mustard gherkins and beetroot.