Wash the potatoes and cook in plenty of boiling water for about 20 minutes. Clean the savoy cabbage, cut in half and cut out the stalk. Cut cabbage into pieces. Blanch in boiling salted water for about 4 minutes
Melt the fat in a pot. Stir in flour and sweat briefly. Add stock and milk while stirring. Bring to the boil, boil for 3-5 minutes. Stir in mustard and season with salt and pepper
Roughly dice the cured pork. Heat the oil in a frying pan and fry the smoked pork in it for about 5 minutes, turning. Coarsely grate the cheese. Rinse potatoes under cold water, drain, peel and slice. Place the savoy cabbage, cured pork loin and potatoes in a greased casserole dish. Spread béchamel on top and sprinkle with cheese. Bake in a preheated oven (electric cooker: 200 °C/ convection oven: 175 °C/ gas: level 3) for approx. 30 minutes