Coat a large nonstick skillet with cooking spray; add olive oil. Place over medium-high heat until hot. Add chicken, and cook 8 to 10 minutes or until chicken is tender, stirring often. Remove from skillet; set aside, and keep warm. Add green pepper and next 3 ingredients to skillet; saute 2 minutes. Add mushrooms; saute 2 minutes. Add broth and next 6 ingredients; cook, stirring constantly, 2 to 3 minutes or until thoroughly heated. Remove from heat, and set aside.
Arrange green beans in a steamer basket over boiling water. Cover and steam 5 minutes or until crisp-tender. Drain well.
Cook pasta according to package directions, omitting salt and fat; drain well. Combine pasta, chicken, tomato sauce mixture, and beans; toss well. Spoon mixture into an 11- x 7- x 1 1/2-inch baking dish coated with vegetable cooking spray. Cover and bake at 350° for 15 minutes. Uncover, sprinkle with shredded cheese, and bake 5 minutes or until cheese melts.