Bring a large pot of salted water to a boil. Add 8 ounces of elbow macaroni and cook according to package instructions until al dente. Drain and set aside.
Make sure your shrimp are peeled and deveined, and your scallops are cooked and chopped into bite-sized pieces. If you haven’t cooked them yet, quickly sauté shrimp and scallops in a little olive oil until opaque and cooked through. Set aside.
In a medium skillet over medium heat, melt 1/4 cup unsalted butter. Once melted, whisk in 1/4 cup all-purpose flour to create a roux. Cook for about 2 minutes, whisking constantly, until slightly golden and smooth. Gradually add 2 cups milk while whisking constantly to prevent lumps. Continue to cook and stir until the sauce thickens, about 5 minutes.
Reduce heat to low and stir in 1 teaspoon garlic powder, 1 teaspoon onion powder, salt, and pepper to taste. Add 2 cups shredded mozzarella cheese and 1 cup grated Parmesan cheese. Stir until cheeses are melted and the sauce is smooth and creamy.
In a large mixing bowl, combine the cooked macaroni, shrimp, chopped scallops, and cheese sauce. Stir gently until everything is evenly coated.
Pour the mixture into a greased 9x13 inch baking dish. Sprinkle 1/2 cup bread crumbs evenly over the top for a crispy crust.
Preheat your oven to 350°F (175°C). Bake the macaroni and seafood for 25-30 minutes or until the top is golden brown and bubbling.
Remove from the oven and sprinkle 2 tablespoons chopped fresh parsley over the top. Let it cool slightly before serving. Enjoy your creamy, comforting Seafood Macaroni Bake!