1. Place first 3 ingredients and water to cover in a large Dutch oven. Bring to a boil over high heat. Cover and reduce heat to medium-low. Simmer 1 hour or until tender. Remove chicken, reserving broth in Dutch oven. Cool chicken completely (about 20 minutes). Discard bay leaf. Skin and bone chicken, and cut meat into pieces.
2. Preheat oven to 350°. Remove and reserve 1/4 cup chicken broth. Bring remaining broth in Dutch oven to a boil over high heat. Break spaghetti into thirds, and cook in broth 12 to 15 minutes or until tender; drain well, discarding broth. Return spaghetti to Dutch oven.
3. Melt butter in a large skillet over medium-high heat. Add onion and next 3 ingredients, and sauté 5 minutes or until tender; add to spaghetti. Stir together soup and 1/4 cup reserved broth; stir into spaghetti mixture. Stir in chicken, tomatoes, and next 3 ingredients. Add salt to taste. Spoon mixture into a lightly greased (with cooking spray) 13- x 9-inch baking dish. Top with cheese.
4. Bake at 350° for 15 to 20 minutes or until cheese melts.