Soak the bread roll in water.
Remove the peel from the onions, cut a lid small at the top of each. Blanch in boiling hot salted water until the individual layers separate easily. Later, hollow out the onion until the 3 outer layers remain.
Chop the inside of the onion and the tops. Rinse the bell bell pepper, remove the stem, core and separating skins and chop into small cubes.
Heat the oil, sauté the onion and the diced bell bell pepper in it and cool.
Mix the minced meat with the squeezed breadcrumbs, the onion and bell pepper cubes and the egg. Season with pepper, mustard, salt and marjoram.
Spread the meat dough evenly into the onions, pressing smoothly with a spoon on the inside. Heat the clarified butter in a gratin dish, put the onions in and sauté briefly.
Now pour the white wine and the clear soup.
Steam in the oven heated to 175 degrees (gas: level 2) for about 45 minutes until soft.
Remove the onions from the mold, arrange on a heated plate.
Mix the cornstarch in a little water and thicken the sauce with it. Season strongly with mustard, salt and freshly ground pepper, mix with the parsley and bring to the table with the onions.
Put the dish in the preheated oven (220 °C) and baste the onions with a little bit of olive oil.
The cooking time is at least 35 min. The onions must be lightly browned and bi