Preheat oven to 350°F (175°C). Grease a 9x13 inch baking dish.
In a large bowl, combine the thawed hash browns, cream of chicken soup, sour cream, 0.5 cup melted butter, cheddar cheese, salt, and pepper. Mix well.
In a separate small bowl, combine the crushed cornflakes and 0.25 cup melted butter.
Spread the potato mixture into the prepared baking dish. Sprinkle the cornflake topping evenly over the potatoes.
Bake for 45 minutes, or until golden brown and bubbly.
Let stand for a few minutes before serving.
Notes
This recipe can be made ahead of time and refrigerated until ready to bake. You can also add diced ham or bacon to the potato mixture for extra flavor.