Wash the potatoes and cook for 15-20 minutes. Clean and wash the leeks and cut the sticks in half. Cover and cook in 600 ml boiling salted water for about 8 minutes. Drain well, collecting the cooking water. Melt the fat. Sweat flour in it.
Add 1/2 litre cooking water, cream, milk and stock while stirring constantly, bring to the boil and simmer for about 3 minutes. Season with salt, pepper and nutmeg. Grate cheese. Drain potatoes, quench, peel and slice. Peel garlic and press it through the garlic press. Fry in hot oil in a pan. Add minced meat and fry until crumbly. Season with salt and pepper. Stir in tomato paste and sauté briefly. Add tomatoes with juice and chop a little bit. Bring to the boil and let it boil down for about 5 minutes. Season to taste with salt and pepper.
Add minced meat and fry until crumbly. Season with salt and pepper. Stir in tomato paste and sauté briefly. Add tomatoes with juice and chop a little bit. Bring to the boil and let it boil down for about 5 minutes. Season to taste with salt and pepper. Put the potatoes into a large greased casserole dish. Pour 3/4 of the béchamel sauce over them. Place the leeks close together on top and cover with the chopped sauce. Pour the rest of the béchamel sauce on top and sprinkle with cheese. Bake in a preheated oven (electric: 200 °C/ gas: level 3) for about 20 minutes. Serve sprinkled with chopped parsley
Put the potatoes into a large greased casserole dish. Pour 3/4 of the béchamel sauce over them. Place the leeks close together on top and cover with the chopped sauce. Pour the rest of the béchamel sauce on top and sprinkle with cheese. Bake in a preheated oven (electric: 200 °C/ gas: level 3) for about 20 minutes. Serve sprinkled with chopped parsley