Preheat oven to 425F (220C). Spray a large baking dish (I used a deep 9 x 13-inch dish) with cooking spray.
In the prepared dish, arrange uncooked linguine in an even layer (breaking the long noodles into smaller pieces as you put them in the dish). In a separate bowl, whisk together chicken broth, onion, garlic and ¼ cup of the Parmesan cheese. Pour chicken broth mixture over the uncooked pasta in the dish and toss gently to combine everything.
Cover tightly with aluminum foil and bake for 40 minutes, stirring halfway through the baking time. Kitchen tongs work really well for tossing and stirring the pasta, if you have them.
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 pasta dish. Top with mozzarella cheese and remaining ¼ cup of Parmesan cheese.
Bake, uncovered, for 5-10 more minutes (or until cheese is melted and shrimp is pink). Keep an eye on it to make sure that you don’t overcook the shrimp.
Stir in a few pats of butter, if desired, and season with salt and pepper, to taste. Garnish with fresh parsley and additional grated Parmesan cheese.
Cooking Just for Two?You can cut all of the ingredients in half and prepare the meal in an 8-inch square baking dish. The cooking instructions and time will remain the same!