Clean and wash the cauliflower and broccoli and divide them into small florets. Peel, wash and chop the carrots. Bring approx. 3/4 litre salted water to the boil. Cook cauliflower for 8 minutes, broccoli for 5 minutes and carrots for 3 minutes. Drain the vegetables and keep the stock. Peel and finely dice the onion.
Sauté onion and minced meat in hot oil for 2-3 minutes. Season with salt and pepper. Grate cheese. Wash and chop parsley. Melt the fat for the sauce. Sweat flour in it. Add 1/2 litre vegetable stock while stirring constantly. Refine with cream. Melt half of the cheese in it. Season to taste with salt, pepper and nutmeg. Fill vegetables and minced meat into an ovenproof dish. Pour sauce over it.
Refine with cream. Melt half of the cheese in it. Season to taste with salt, pepper and nutmeg. Fill vegetables and minced meat into an ovenproof dish. Pour sauce over it. Sprinkle with remaining cheese. Bake in a preheated oven (electric cooker: 200 °C/ gas: level 3) for about 20 minutes. Serve sprinkled with parsley