Chopped onion, garlic, celery and sauté in the oil with 3 tbsp water for about 4-5 minutes. Add chopped parsnips and beets, broth and 1-1.2 liters of cold water. The soup to the boil, reduce the temperature and leave are simmer about 30 minutes. Add vinegar and chopped potatoes, boil 10-15 minutes to complete softening of vegetables. The soup is served, garnished with dill.