Sweet and Sour Roast

Preparation:

Preparation: Peel and cut the onions and the cleaned and washed leek into rings. Soften everything in a saucepan with 3 tablespoons of oil, 20 g of butter and 1 pinch of sugar, add salt and pepper and pour in the broth, vinegar and tomato puree; cover and simmer for 20 minutes. Slice the meat, put it in the casserole, let it flavor with the sauce for 10 minutes and sprinkle with chopped parsley.