COOK pasta as directed on package, omitting salt.
MEANWHILE, crumble sausage into large skillet sprayed with cooking spray. Add onions; cook on medium heat 8 min., stirring frequently. Stir in peppers; cook 4 to 6 min. or until sausage is evenly browned, stirring frequently. Add dressing; mix well. Simmer on medium-low heat 8 to 10 min. or until peppers are crisp-tender.
DRAIN pasta, reserving 1/2 cup cooking water. Add pasta and reserved water to sausage mixture in skillet with 1/2 cup cheese; mix well. Sprinkle with remaining cheese.
serving size = 2 cups (500 mL)