COOK pasta as directed on package.

MEANWHILE, cook sausage in large nonstick skillet on medium-high heat 10 min. or until sausage is cooked through, stirring occasionally. Drain sausage; return to skillet. Add tomatoes with their liquid, the onions and dressing. Cook 5 min. or until onions are crisp-tender, stirring occasionally.

DRAIN pasta. Toss with the sausage mixture and 1/2 cup of the cheese. Sprinkle with the remaining 1/4 cup cheese.