Rinse the chicken and remove the inside parts. Place the chicken in a large stockpot, add the chicken broth, and then add enough water to cover the chicken. Bring the chicken in broth to a boil, if there is visible fat, skim it and discard. Reduce to a simmer and cook until the chicken is tender, about 2 hours.
Remove the chicken from the broth to a cutting board and let it rest until it's cool enough to handle. Skim the top of the broth, or run the broth through a strainer to get rid of anything floating around. Then add the onion, carrots, celery, garlic and parsnip to the broth. Bring back to a boil. Reduce to a simmer, and cook the veggies until tender (about 20 minutes). Shred the chicken apart, then add back to the soup. Stir in the parsley and dill. Taste and add salt and pepper. If you want noodles in the soup, add them to the broth, bring to a boil again and simmer for 8 to 10 minutes (or until the noodles are tender).