Soak the bun in water. Peel the onion and cut into very fine cubes. Wash the liver, pat dry, remove all cuticles and tendons. Puree the liver in a blender or turn it through the fine slice of the meat grinder and add to 70 g of mixed minced meat with the onion cubes. Beat 25 g butter in a cup with a fork until frothy and fold into the meat dough with the egg, the squeezed out bun and 2 heaped tablespoons of breadcrumbs. Season well with salt, pepper, thyme, marjoram, caraway seeds and nutmeg and mix well.
Bring the broth to a boil. Using 2 coffee spoons, cut off small dumplings from the meat mixture and let them steep in the broth for about 6 - 8 minutes (do not boil !!!).
Serve the soup sprinkled with the chopped fresh parsley.