Preheat the oven to 350°F and lightly grease a 9-by-13-inch baking dish.
Stir the cream of chicken soup, sour cream, onion powder, garlic powder, salt, and pepper together until smooth.
Fold in the shredded chicken, then spread the mixture evenly in the prepared baking dish.
Sprinkle the cheddar cheese over the filling.
Toss the crushed crackers with the melted butter and sprinkle them evenly over the casserole.
Bake uncovered for 25 to 30 minutes, until bubbling and golden. Rest for 5 minutes before serving.