Wash the meat and dab dry. Rub with salt and pepper. Place on the fat pan, pour hot clarified butter over it and bake in the preheated oven (electric cooker: 200 °C/ gas: level 3) for two hours.
For the crust, peel the garlic and cut into slices. Pluck the mint leaves. Heat the oil. Fry garlic and breadcrumbs until golden brown. Add lemon zest, juice, mint and crushed peppercorns.
In the meantime, clean, wash and cut the beans into small pieces. Just before serving, cook them in boiling salted water for 15 minutes. Peel and wash the potatoes, cut out balls or cut them into quarters.
Also cook in boiling salted water for ten minutes, remove and rinse. Wash the tomatoes and dab them dry. Deglaze the roast with white wine ten minutes before the end of the cooking time. Add potatoes and tomatoes to the stock.
Spread the prepared crust over the roast. Serve leg of lamb and vegetables garnished with mint and lemon slices.