Peel and finely dice the onion and garlic. Mix mustard, ketchup, sugar, onion and garlic. Season with salt and pepper. Wash the leg, cut off excess fat. Spread the meat with the seasoning paste and place on the fat pan. Roast in the preheated oven (electric cooker: 175 °C/circulating air: 150 °C/gas: level 2) for approx. 2 1/2 hours
Wash the rosemary. Pluck and chop all but a few needles for garnishing. Peel, wash and slice the potatoes. Mix with coarse salt, cayenne pepper and rosemary. Distribute around the leg about 40 minutes before the end of the frying time
Remove the leg and potatoes and keep warm. Dissolve the meat with wine. Bring to the boil in a pot with approx. 300 ml water and stock and simmer briefly. Season sauce to taste. Arrange everything and garnish with rosemary. Green beans taste good with it
Drink: strong red wine, for example Merlot Cabernet Sauvignon from Montana