Preheat your oven to 350°F (175°C).
Boil a large pot of salted water and cook the jumbo pasta shells according to package instructions until al dente. Drain and set aside.
In a mixing bowl, combine the cooked chicken, broccoli, 1 cup of cheddar cheese, cream of chicken soup, milk, garlic powder, onion powder, salt, pepper, and paprika. Stir well to combine all ingredients.
Gently fold in the cooked pasta shells, ensuring they are evenly coated with the chicken and broccoli mixture.
Transfer the mixture into a greased baking dish and spread evenly.
Top with the remaining 1 cup of cheddar cheese and sprinkle the grated Parmesan cheese on top.
Cover the dish with aluminum foil and bake in the preheated oven for 20 minutes.
Remove the foil and bake for an additional 10 minutes or until the cheese is bubbly and golden brown.
Remove from the oven, let it cool for a few minutes, then serve warm.