Spray 12-inch skillet or Dutch oven with nonstick cooking spray. Add chicken and onion; cook and stir over medium-high heat for 4 to 6 minutes or until chicken is browned and onion is tender.
Add all remaining ingredients except parsley; mix well. Bring to a boil. Reduce heat; cover and simmer 15 to 18 minutes or until vegetables and noodles are tender and chicken is no longer pink, stirring occasionally. Sprinkle with parsley.