Bring 8 cups of water to a boil in a large stock pot
Add the diced onion, parsley root or celery, parsnip and carrots along with the soup bones into the boiling pot of water.
Soak the bread in a bowl of water and then squeeze out the excess water and mash the bread with a fork.
Mix the ground beef and pork with the minced onion, the mashed bread, rice and season with salt and pepper. Mix together thoroughly and make small meat balls with wet hands.
When the vegetables become fork tender, skim off any fat from the soup bones and add in the meat balls to the boiling water.
Reduce heat to simmer, cover and cook for 30-40 minutes.
When the soup is almost done and the meat balls have risen to the top, add in the tomato paste and stir.
Finely chop the lovage or parsley and celery leaf and add it to the soup.
Season with salt and pepper to taste
Add in the vinegar and stir. Remove the soup bones before serving.
This soup would traditionally be served with sour cream and a hot pepper on the side which I would highly recommend.