In a separate, preferably narrow saucepan, boil 1 liter of water, add vinegar. In a bucket greased with sunflower oil, gently break the egg and lower it into boiling water. Cook the egg for 2 minutes. Pour the soup into a bowl, remove the poached egg with a slotted spoon and transfer it to a bowl with soup. The same should be done with the remaining portions. Garnish the soup with parsley or dill leaves.