1Cook and drain macaroni as directed on package, omitting salt and adding peas for the last 5 minutes of cooking.
2Meanwhile, in 10-inch nonstick skillet, heat milk, cream cheese and American cheese over medium-low heat, stirring carefully with wire whisk, until cheese is melted.
3Add cooked macaroni and peas to cheese sauce; stir to coat. Let stand 2 to 3 minutes or until slightly thickened. Serve topped with croutons.