Step 1

Preheat the oven to 350°F. Pour the melted butter into a 9x13-inch baking dish and swirl to coat.

Step 2

In a large mixing bowl, stir together the sour cream, cream of chicken soup, 2 cups of shredded cheddar, onion, salt, and pepper. Fold in potatoes until well coated.

Step 3

Spoon the mixture into the prepared baking dish and sprinkle with the remaining cup of cheddar cheese.

Step 4

Bake for 45 to 50 minutes or until the casserole is bubbling and beginning to brown at the corners. Let cool for 15 minutes before serving.