Heat oven to 400°F. Spray 2-quart casserole with cooking spray. Cook and drain pasta as directed on package.
Meanwhile, in 3-quart saucepan, heat soup and milk to boiling. Remove from heat; stir in cheeses until melted. Stir in pasta. Spoon into casserole
Bake uncovered 20 minutes or until edges are bubbly. Refrigerate leftovers.