In the meantime, clean the leek and cut into rings approx. 2 cm wide. Fry the minced meat in oil, then add the leek and sauté briefly. Add the cream, simmer briefly and season with salt, pepper and nutmeg. Mix the spaghetti with the leek mince sauce in a baking dish, sprinkle with the cheese, and bake in a preheated oven for about 15-20 minutes at 200-220 degrees.