Fry the breadcrumbs in 5 tablespoons of hot butter. Cool down. Peel and chop onion. Peel or clean, wash and chop carrots, kohlrabi and leek.
Barely 1⁄4 l Bring slightly salted water to the boil. Steam vegetables for about 5 minutes. Pour off, collecting the vegetable water. Heat 3 tablespoons of butter. Sauté onion in it. Dust with flour and sauté briefly.
Stir in vegetable water and milk, bring to the boil. Simmer for about 5 minutes. Grate cheese. Melt half in the sauce. Season to taste with salt, pepper and nutmeg. Wash and chop parsley and stir into the sauce.
Put the vegetables and sauce in a greased casserole dish. Coarsely chop the almonds. Mix with butter crumbs and remaining cheese. Sprinkle over the vegetables. Bake in the preheated oven (electric cooker: 200 °C/circulating air: 175 °C/gas: see manufacturer) for 20-25 minutes.