Peel the onions and chop one of them finely. Saute in 1 tablespoon of oil until translucent and remove from heat. Place the bread into a bowl and soak in the hot milk for 10 minutes. Mix together the sauteed onion, soaked bread, egg, parsley and marjoram. Season with salt, pepper and nutmeg.
Rinse the veal breast and pat dry. Cut a pocket. Put the bread stuffing inside. Do not over-fill. Tie with kitchen twine or skewer to hold together.
Preheat the oven to 180°C (approximately 350°F).
Peel and coarsely chop the carrots, celery and remaining onions. Rinse the bones and pat dry.
Season the breast with salt and pepper and sear on all sides in a roasting pan in the remaining hot oil. Remove and cook the chopped vegetables with the bones 10-15 minutes until brown. Deglaze with the broth and put the veal back in. Cook in the oven for 2.5 hours, regularly basting with the beer and adding broth as needed. In the last 30 minutes, add the rosemary.
Before serving, remove the skewers or kitchen twine and season the sauce.