Wash the chives, shake dry and cut into fine rolls. Peel garlic and chop finely. Knead minced meat, garlic, breadcrumbs, egg, mustard and chives, season with salt and pepper and form into small balls.
Heat 2 tablespoons of oil in a frying pan and fry the balls for about 4 minutes, turning them over. Prepare noodles in boiling salted water according to instructions on the packet.
Peel, wash and cut the carrots into small cubes. Wash and clean the leek and cut into rings. Peel and finely chop the onion. Heat 2 tablespoons of oil in a saucepan. Sauté the onion in it until transparent.
Add the carrots and leek and continue steaming for about 3 minutes. Deglaze with stock and 500 ml water, season with salt, pepper and nutmeg, simmer for about 10 minutes.
Drain the pasta. Wash the spinach and dab dry. Finely slice the cheese. Add the noodles, meatballs and spinach to the soup shortly before the end of cooking time. Sprinkle cheese over the soup.