Cook pasta according to package directions, omitting salt and fat. Drain.
Coat a nonstick skillet with cooking spray; place over medium-high heat until hot. Add onion and garlic; sauté 5 minutes. Add tomatoes, Worcestershire sauce, seasoning, and salt; bring to a boil. Reduce heat, and simmer, uncovered, 10 minutes. Stir in 1 cup cheese, cooked spaghetti, and chicken. Spoon into a 3-quart casserole coated with cooking spray. Sprinkle with remaining 1 cup cheese. Bake at 350º for 15 minutes.
Used fresh onions and boiled the chicken breasts. I don't think I got the 9 ounces of spaghetti correct, a little too much. Wonderful flavor and once the chopping was done, quite easy to put together. A definite repeat.
cmaranski--try adding some sauteed squash (zucchini or yellow or both). Sauteed mushrooms would probably work well too. In fact, you could substitute portabellos for the meat, for a very satisfying dish.
This has potential but is lacking greatly. I added a lot more garlic and italian seasoning. I also added some parmesean cheese, red wine and heavy cream to make a thicker sauce. Great recipe to experiment with.