Peel, wash and chop the potatoes. Cook in salted water for about 20 minutes
Clean and wash the leek and mushrooms. Cut the leek into pieces, halve the mushrooms. Wash the meat, dab dry and remove the bone. Dice meat. Cut cucumber into slices
Heat the oil. Brown the meat in it in portions. Take out. Fry the mushrooms in the frying fat until golden brown. Add leek and fry for about 5 minutes. Season vegetables with pepper and a little salt
Heat the milk. Drain potatoes, mash. Add milk and melt 2 tablespoons of fat in it. Season puree with salt, pepper and nutmeg
Put 2/3 of the puree into a greased casserole dish. Spread the vegetables, celery and cucumber on top. Add the rest of the puree. Spread 1 tablespoon of fat in flakes on top. Bake everything in a preheated oven (electric cooker: 200 °C / fan oven: 175 °C / gas: level 3) for approx. 25 minutes
Drink: cold beer