In a large stockpot simmer chicken and onion in water for 25 minutes or until juices run clear when chicken is pierced
Remove chicken from stockpot and set aside
To broth, add tomatoes, carrots, green pepper, potatoes, pepper, rosemary, Italian seasoning and garlic
Simmer vegetables while cutting chicken breasts into bite-size pieces; add to stew.
Continue to cook on low for an additional 30 minutes or until carrots and potatoes are tender
Add rice and let simmer 10 minutes longer.