Preheat your oven: Begin by preheating your oven to 350°F (175°C). Grease a 9x13-inch baking dish to prevent sticking.
Mix the filling: In a large mixing bowl, combine 4 cups cooked, shredded chicken, 8 oz softened cream cheese, 1 cup sour cream, 1 cup cottage cheese, 1 cup mozzarella cheese, 1/2 cup Parmesan cheese, 1 can cream of chicken soup, and the spices (1 teaspoon garlic powder, 1 teaspoon onion powder, 1 teaspoon salt, and 1/2 teaspoon pepper). Mix until all ingredients are thoroughly combined.
Spread the mixture: Transfer the chicken mixture into the prepared baking dish, spreading it evenly to fill the dish.
Prepare the topping: In a separate bowl, combine 2 cups crushed Ritz crackers with 1/4 cup melted butter, stirring until the crackers are evenly coated.
Add the topping: Evenly sprinkle the crushed cracker mixture over the chicken filling in the baking dish.
Bake the casserole: Place the dish in the preheated oven and bake for 30-35 minutes, or until the casserole is bubbly and the topping is golden brown.
Cool and garnish: After removing the casserole from the oven, let it cool slightly before garnishing with fresh parsley if desired.
As you prepare this casserole, keep an eye on the baking time and look for visual cues: the edges should be slightly bubbling, and the top should have that perfect golden crust. If you want a crispier topping, you can broil it for an additional 1-2 minutes at the end, but keep a close watch to avoid burning.