Preheat oven to 350 degrees. Coat a casserole dish with cooking spray.
- Cook 1 cup dry whole-grain elbow macaroni in boiling water according to package directions. Drain and set aside.
- Dice 1 medium tomato, 1 medium green bell pepper and 1 small onion. Add the vegetables to the macaroni, and toss together. Set aside.
- In large saucepan melt 1 tablespoon no-trans-fat margarine. Stir in 1 tablespoon all-purpose flour and ¼ teaspoon ground white pepper; whisk if necessary to blend until smooth. Stir in 1½ cups low-fat milk. Cook over medium heat until thickened. Add 8 ounces shredded reduced-fat cheddar or Colby Jack cheese. Stir until melted. Let simmer gently for a few minutes.
- Stir in macaroni and vegetable mixture. Pour into casserole dish. Bake in oven until bubbly at the edges.
Makes 2-3 servings.