Preheat the oven to 350°F (175°C). Lightly grease a 9x13-inch baking dish.
In a large bowl, mix together cream cheese, sour cream, cottage cheese, shredded cheddar cheese, garlic powder, onion powder, salt, and pepper until smooth.
Fold in the cooked chicken until well combined.
Spread the mixture evenly into the prepared baking dish.
In a small bowl, mix crushed Ritz crackers with melted butter.
Sprinkle the cracker topping evenly over the casserole.
Bake for 30–35 minutes, or until hot and bubbly.
Let cool for 5 minutes before serving. Garnish with parsley if desired.