Preheat oven to 350°F and lightly grease an 8x8-inch baking dish.
Soften the cream cheese until easy to stir.
Mix cream cheese, sour cream, cream of chicken soup, garlic powder, salt, and pepper until smooth.
Stir in half a cup of cheddar cheese.
Fold in the cooked chicken until evenly coated.
Spread the chicken mixture evenly in the prepared baking dish.
Sprinkle the remaining cheddar cheese over the top.
Mix crushed crackers with melted butter and scatter them evenly over the cheese.
Bake uncovered for 25–30 minutes, until hot, bubbling, and golden.
Rest for 5–10 minutes before serving.