Preheat oven to 425°F (220°C).
In a 9 x 13-inch baking dish, stir together uncooked pasta, Alfredo sauce, chicken broth, tomatoes, spinach, and garlic. Cover tightly with aluminum foil and bake for 30 minutes.
Uncover; give the pasta a good stir. At this point you should check the pasta to make sure that it is al dente (firm but with a tender bite). I have had good luck with the 30-minute cook time; however, the cooking time will vary based on your oven and on the type of dish that you use. If it’s still too hard after 30 minutes, just cover the dish and return to the oven for 10-15 more minutes, or until the pasta is al dente. Then move on to the next step.
Stir in the chicken, and sprinkle the cheese over top. Bake uncovered for 5-10 more minutes (or until cheese is melted and pasta is tender).
Garnish with chopped fresh basil and grated Parmesan right before serving.
