Preheat the oven to 425°F. Spray a 9 x 13-inch baking dish with nonstick cooking spray.
In the prepared dish, whisk together the broth, wine, garlic, Italian seasoning, and salt.
Add the uncooked pasta and the onion to the dish, making sure that everything is evenly distributed and submerged in the liquid.
Cover tightly with aluminum foil and bake for 40 minutes, stirring about halfway through. Tip: kitchen tongs work really well for tossing and stirring the pasta.
Uncover; stir again. 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.
Stir the raw shrimp into the dish, along with a few pats of butter for extra flavor if you like. Top with mozzarella and Parmesan.
Bake, uncovered, for 5-10 more minutes, or until the cheese melts and the shrimp turn pink.
Garnish with fresh parsley and additional grated Parmesan cheese.