Cover the bacon bones with water and bring to the boil. Simmer for approx. 2 hours skimming off any fat. Dice the sweet potato and carrot and put in the saucepan with the bacon bones. Add the dried herbs and salt/pepper to taste. Shred cabbage and put in pot when sweet potato and carrot is almost cooked (you may need to add water at this stage to cover the cabbage). Remove bacon bones from the soup, and let cool. Blend the remainder of the soup. Returning any shredded bacon bits you can get off the bones.