Dice the garlic cloves and place in a mortar. Pluck 1 stalk of rosemary, 1 stalk of thyme and 2 - 3 sprigs of oregano and add 1 level teaspoon of salt to the garlic. Mortar well and mix with the mustard.
Lightly salt and pepper the inside of the boned leg of lamb, then apply the spice paste and tie the leg in shape. Salt, pepper and fry in a roasting pan with clarified butter.
Roast the chopped soup greens and the onion cut into wedges and pour the meat stock over them.
Cook the roast in the preheated oven at 180 ° C top / bottom heat for a good 1 hour. Pour in the wine halfway through the cooking time. When the cooking time is over, wrap the roast in aluminum foil and keep it warm in the switched off stove.
Brush the meat stock with the vegetables through a hair sieve, season to taste, bind if necessary and extend with the cream.
Side dishes to your taste. Personally, I prefer boiled potatoes, green beans, and a tomato salad.