Wash meat thoroughly and pat dry with kitchen paper. Season the meat with pepper. Sprinkle salt evenly on a fat pan of the oven and place the meat on top.
Roast in the preheated oven (electric cooker: 175 °C/ gas: level 2) for about 2 1/4 hours. 30 minutes before the end of the roasting time, brush the roast with mustard and sprinkle with pepper. Quarter the savoy cabbage, clean, wash and cut into strips.
Clean, wash and slice the carrots. Wash potatoes thoroughly and cook in boiling salted water for about 20 minutes. In the meantime peel and finely dice the shallots. Wash parsley, dab dry and chop finely.
Peel and finely dice the onions. Heat the oil in a casserole dish. Add the onions, savoy cabbage and carrots and braise over medium heat for about 12 minutes, turning. Drain the potatoes, rinse briefly and peel and slice the warm potatoes.
Butter in a small pan, fry shallots in it and add parsley. Pour the herb and shallot butter over the potatoes. Sprinkle the roast and vegetables with pepper and arrange on a plate, garnished with parsley as desired.
Add extra potatoes.