Directions

1. Preheat oven to 350°F. Lightly coat a 3-quart rectangular baking dish with nonstick cooking spray; set aside. Cook pasta al dente according to package directions. Drain, and transfer to prepared baking dish.
2. Meanwhile, season chicken with salt and pepper to taste. In a large skillet cook chicken in enough water to cover. Simmer 15 to 20 minutes or until chicken is no longer pink (165°F). Drain; cool slightly. Cut into bite-size pieces. Add to pasta in baking dish.
3. Using the same skillet, heat butter over medium heat. Stir in mushrooms, onion, celery and bell pepper; cook and stir until tender. In a small bowl whisk together flour and broth. Add to skillet. Cook until mixture is thickened and bubbly, stirring occasionally. Stir in milk, pimiento, ginger and nutmeg. Cook until heated through. Season with salt and pepper to taste. Pour over pasta mixture in baking dish. Toss gently to coat.
4. Cover and bake 10 minutes. Remove baking dish from oven. Sprinkle with cheese. Bake, uncovered, 10 minutes more or until bubbly and cheese is melted. Let stand 5 minutes before serving.