Preheat the Oven:
Preheat your oven to 350°F (175°C). Grease a 9×13-inch baking dish or casserole dish.
Mix the Filling:
In a large bowl, combine the softened cream cheese, sour cream, mayonnaise, mozzarella, cheddar, garlic powder, onion powder, salt, and pepper. Stir until the mixture is smooth and creamy.
Fold in the shredded chicken until evenly coated with the cream cheese mixture.
Assemble the Casserole:
Spread the chicken mixture evenly into the prepared baking dish.
Prepare the Cracker Topping:
In a small bowl, mix the crushed Ritz crackers with the melted butter until the crumbs are well-coated.
Sprinkle the buttered cracker crumbs evenly over the chicken mixture.
Bake:
Bake the casserole in the preheated oven for 25-30 minutes, or until the top is golden brown and the casserole is bubbling around the edges.
Garnish and Serve:
Remove from the oven and let it cool for a few minutes.
Garnish with fresh parsley, if desired, and serve warm.
