Toss chicken with next 3 ingredients in large bowl until evenly coated. Cook in large nonstick skillet on medium-high heat 8 min. or until evenly browned, stirring frequently. Remove from skillet; set aside.
Add peppers to skillet; cook and stir 2 min. Stir in vinegar; cook 1 min. or until vinegar is cooked off. Return chicken to skillet with tomatoes; stir. Cover; simmer on medium-low heat 15 min. or until heated through.
Top with cheese; let stand, covered, 2 min. or until melted.