Preheat oven to 425 degrees F. Spray your largest baking dish (I used a deep 9 x 13-inch dish) with cooking spray.
In the prepared dish (or in a separate bowl), whisk together the Alfredo sauce, chicken broth, sour cream, paprika and salt until smooth and completely combined. Stir in the uncooked noodles, onion, uncooked chicken and garlic. Cover tightly with aluminum foil and bake for 30 minutes.
Uncover; stir. At this point you should check the pasta to make sure that it is al dente (firm but just about finished cooking). If it’s still too hard, cover the dish and return to the oven until pasta is al dente. Then move on to the next step.
Remove the cover from the dish. Return dish to the oven (uncovered) and bake for for 10 more minutes (or until pasta is tender, chicken is cooked through, and sauce has thickened).
Give it a good stir, dust with sprinkling of smoked or spicy paprika, and garnish with chopped fresh parsley or dill.