Cook macaroni to desired doneness as directed on package. Drain.
Heat oven to 350°F. Spray 2-quart casserole with nonstick cooking spray. In large bowl, combine cooked macaroni and all remaining ingredients except cornflake crumbs; stir to combine. Pour mixture into sprayed casserole; sprinkle with cornflake crumbs.
Bake at 350°F. for 25 to 35 minutes or until thoroughly heated.