Place chicken breasts in a large skillet; add broth. Cover and bring to a boil over medium-high heat. Reduce heat to medium-low, and simmer, covered, 30 minutes or until done. Remove chicken from skillet, and let stand 15 minutes or until cool to touch. Pulse chicken in food processor until finely chopped, stopping to scrape down sides.
Combine chicken, celery, bell pepper, and onion in a large bowl. Stir mayonnaise and next 3 ingredients into chicken mixture. Cover and chill at least 4 hours. Store any remaining chicken salad in an airtight container up to 1 week in refrigerator.