Soak rolls in cold water. Peel onions and, except for one, dice them coarsely. Cut remaining onion into rings. Squeeze the bread roll and knead with the minced meat, egg, diced onion, 1 heaped tablespoon of mustard, marjoram, salt and a little pepper.
Form 8 meatballs, wrap each with a slice of bacon and pin them with a wooden skewer. Heat the oil in a pan and fry the minced medallions for about 8 minutes, turning them over. Add the onion rings approx. 2 minutes before the end of the frying time and fry as well. Serve the medallions with a dash of mustard, onion rings and some fresh marjoram if desired