Cut the carrots, celery and kohlrabi into cubes. First add the carrots for about 5 minutes, then the kohlrabi and celery and cook until cooked in the broth and all the specified spices. Then drain everything through a sieve, but collect the broth. Heat the margarine and stir in the flour. Deglaze with the stock and let it boil through. Fold in the vegetables and season again with salt, nutmeg, pepper and vinegar. Sprinkle with finely chopped parsley.
Serve the whole thing with potatoes and meatballs.