Wash the meat, dab dry and rub with salt and pepper. Place meat on the fat pan of the oven and roast in the preheated oven (electric: 200 °C/ gas: level 3) for approx. 1 1/2 hours.
Gradually add 1/2 litre of water. In the meantime, crumble toast finely and mix with mustard and egg. Spread the bread-mustard mixture on the roast 20 minutes before the end of the cooking time. Clean and wash the vegetables.
Cut carrots into sticks, cabbage into large pieces. Cook vegetables in boiling salted water for about 8 minutes. Take out meat, keep warm. Deglaze the meat with broth and pour it through a sieve into a pot.
Add cream and bring to the boil. Stir in sauce thickener, bring to the boil again. Season to taste with mustard, salt and pepper. Drain vegetables. Heat the fat and toss the vegetables in it. Arrange meat, vegetables and some sauce on a plate.
Garnish with parsley. Remaining sauce extra is enough.