HEAT oven to 375°F.
HEAT large heavy nonstick skillet on medium heat. Add chicken; sprinkle with 1 tsp. thyme. Cook 5 min. on each side or until each breast is lightly browned on both sides.
MEANWHILE, combine stuffing mix and hot water in 13x9-inch baking dish sprayed with cooking spray; spread into even layer in dish. Spoon vegetable blend into 6 mounds over stuffing, using about 1/2 cup of the vegetable blend for each mound; top each with 1 chicken breast.
COOK cream cheese spread and milk in saucepan on medium heat 4 min. or until cream cheese is completely melted, stirring constantly. Spoon over chicken; sprinkle with cheese and remaining thyme.
BAKE 25 min. or until chicken is done (165ºF).