This was a staple in my family when I was growing up. We would have it at least once a week. It is a great tasting and inexpensive soup to make. Great with freshly baked gluten-free buttered bread! Even those who don't really like cabbage all that much, like this soup.
Now, my Mom used to use a can of Heinz tomato soup for the base of this soup, this was before I was diagnosed with celiac disease. I find using Amy's gluten-free tomato soup is a good substitute. Basically any gluten-free tomato soup works. If you can't find soup or don't have time to make your own, then a can of crushed tomatoes with a tablespoon of sugar should work. I sometimes use tomato juice or V8 vegetable juice. You can add a small can of the V8 vegetable juice if you'd like to up the veggie content.
The star anise seed is important to the flavour of this soup. If you can't find star anise seed (the star-shaped black seed in the photo) it is not the end of the world. The soup will still taste good, but it will be missing the unique slightly sweet taste this spice gives the soup.
You may be familiar with Beet Borscht. This is a type of cabbage borscht is usually associated with Mennonites (Russian or German background). In my family we have Mennonite heritage from my Mon's side of the family. Each family adjusts the ingredients to their tastes. Which borscht do you prefer? Beet? or Cabbage? I like both.
If you are looking for other gluten-free soups why not check out my Split Pea and Ham Soup. It is delicious and satisfying. Here is a link to the recipe if you are interested.
Note: These are my personal experiences and opinions. Always seek out a medical opinion for medical concerns.