COOK pasta as directed on package, omitting salt.
MEANWHILE, heat dressing in large nonstick skillet on medium-high heat. Add chicken, onions, carrots and peppers; stir. Cover; simmer 7 min. or until chicken is done, stirring occasionally. Stir in tomatoes; simmer 2 min.
DRAIN pasta; place in large bowl. Add chicken mixture; mix lightly. Sprinkle with cheese.