Step 1

Preheat the oven to 350 degrees Fahrenheit. Grease a 9x13-inch glass baking dish with butter or non-stick spray.

Step 2

Melt 1 tablespoon of butter in a skillet over medium heat. Add the onion and stir and cook until soft and translucent. Remove from heat.

Step 3

Melt 1/2 cup of butter in the microwave.

Step 4

In a large bowl, combine the sauteed onions, hash browns, 1/2 cup of melted butter, cream of chicken soup, sour cream, cheese, salt, and pepper. Spoon the mixture into the greased baking dish.

Step 5

Melt the remaining 3 tablespoons of butter in a large skillet over medium heat. Add the cornflakes and stir until lightly browned, about 2 to 3 minutes. Spread the cornflakes evenly over the casserole.

Step 6

Bake for 40 to 45 minutes. Allow the casserole to cool slightly before serving. Enjoy!