Wash the meat and dab dry. Put it on the fat pan and pour hot clarified butter over it. Bake in the preheated oven (electric: 200 °C/ gas: level 3) for 50-60 minutes.
After each approx. 20 minutes, pour 200 ml of water over it. In the meantime, peel and finely chop 1 onion for the crust. Wash and chop the herbs. Mix onions, herbs, pepper, lemon peel, oil and coarse salt.
Spread on the roast about 10 minutes before the end of the frying time. For the vegetables, peel the remaining onions and cut in half. Wash, clean and slice the tomatoes and zucchini. Melt the sugar in a pan until golden brown.
Deglaze with vinegar and roast stock, bring to the boil and season with salt. Cook onions for about 10 minutes, remaining vegetables for about 5 minutes and season again. Arrange roast and vegetables on a plate and serve garnished with herbs.