Preheat your oven to 350°F (175°C). Lightly grease a 9x13-inch casserole dish with cooking spray or butter.
In a large mixing bowl, combine softened cream cheese, sour cream, cream of chicken soup, mayonnaise, garlic powder, onion powder, salt, and pepper. Mix until smooth and creamy.
Add shredded chicken and 1 ½ cups of the cheddar cheese to the creamy mixture. Stir gently until all ingredients are evenly coated.
Spread the chicken mixture evenly into the prepared baking dish, smoothing the top with a spatula.
In a small bowl, combine crushed Ritz crackers with melted butter. Stir until every crumb is coated.
Sprinkle the buttery cracker mixture evenly over the chicken base. Top with the remaining ½ cup cheddar cheese.
Bake uncovered for 30–35 minutes, or until the casserole is bubbling around the edges and the topping is golden brown.
Remove from oven and let rest for 5–10 minutes before serving. Garnish with fresh parsley if desired.
