In a large dutch oven or stock pot, heat oil ver medium heat, adding bacon. Cook bacon until most of the fat has rendered out. Add onions, celery, carrots, potatoes and garlic to the pot and cook until onion is translucent. Add fresh cabbage and cook until tender. Add ham bone or hock, kielbasa, sauerkraut, tomatoes quickly crushed in your hand , beef stock, paprika, bay leaf and sugar. Stir ingredients together and bring to a boil. Reduce heat to mediium low and cook about 2 hours or until meat falls from the bones.

Remove ham bone or hock from the soup, let cool slightly and remove all bones and cartilage from meat. Chop meat into bite-size pieces, if necessary, and return to the pot. If you prefer a slightly more sour soup, add some of the reserved sauerkraut juice.

Cool the soup in an ice-water bath and then refrigerate. The next day, skim off the congealed fat and reheat. Adjust seasonings, if necessary. Serve in warmed bowls with a dollop of sour cream and sprinkle chopped parsley, if desired.