Clean, wash and cut the leek into rings. Peel onions, cut into rings.
Heat 2 tablespoons of oil in a large frying pan. Fry the smoked pork on each side for 2-3 minutes. Toast the bread and place it in a greased casserole dish. Place meat on top. Preheat oven (electric cooker: 200°C/circulating air: 175°C/gas: see
Heat 1 tablespoon of oil in the frying fat. Fry the leek and onions for about 4 minutes, turning them over. Dust with flour and sauté briefly. Add cream and milk, bring to the boil. Simmer for about 5 minutes while stirring.
Season with pepper and nutmeg. Spread over the meat. Grate cheese directly over it. Bake in a hot oven for 10-15 minutes.