Step 1. Cook the pasta. Bring a large pot of salted water to a boil and cook the pasta until it is just al dente. You want it slightly undercooked since it will continue to cook in the oven. Drain well and set aside.
Step 2. Prepare the chicken mixture. In a large mixing bowl, combine the cooked chicken with Alfredo sauce, ricotta cheese if using, half of the mozzarella, half of the Parmesan, garlic powder, Italian seasoning, salt, and pepper. Stir until everything is evenly coated and creamy.
Step 3. Combine with pasta. Add the drained pasta into the chicken mixture and gently fold it together until the pasta is fully coated with sauce. Take your time to make sure every piece of pasta is well covered so the bake turns out creamy in every bite.
Step 4. Transfer to the baking dish. Grease a 9×13 inch baking dish and spread the pasta mixture evenly inside. Smooth out the top with a spatula so it bakes evenly. Sprinkle the remaining mozzarella and Parmesan cheese on top.
Step 5. Bake until golden. Place the dish in a preheated oven at 375°F and bake uncovered for about 25 to 30 minutes, or until the cheese is melted, bubbling, and golden brown around the edges. If the top browns too quickly, cover loosely with foil during baking.
Step 6. Garnish and serve. Remove from the oven and let it rest for a few minutes before serving. Sprinkle with fresh parsley for color and freshness. Serve warm with garlic bread and a simple salad for a complete meal.