HEAT dressing in large nonstick skillet on medium-high heat. Add chicken; cook 10 min. or until chicken is lightly browned on both sides, turning occasionally.
ADD tomatoes, tomato paste, peppers and garlic; mix well. Cover; simmer on medium-low heat 20 min. or until chicken is done (170°F), stirring occasionally. Meanwhile, cook spaghetti as directed on package.
REMOVE skillet from heat. Add Parmesan to chicken mixture; stir. Sprinkle with mozzarella; cover. Let stand 5 min. or until mozzarella is melted. Drain spaghetti; place on platter. Top with chicken and sauce.