HEAT 3 Tbsp. dressing in large skillet on medium-high heat. Add chops; cook 5 to 6 min. or until done (145ºF), turning after 3 min. Transfer to plate; cover to keep warm.
ADD remaining dressing, onions and apples to skillet; cook 3 min. or until apples are slightly softened, stirring frequently. Add water and sugar; stir. Cook on medium-low heat 3 min., stirring occasionally. Meanwhile, prepare stuffing as directed on package.
RETURN chops to skillet. Spoon onion mixture over chops, then spoon stuffing around edge of skillet; cover. Cook 5 min. or until stuffing is heated through.