Cheesy Hash Brown Cassole with a Crispy Topping

Ingredients

• 1 (32-ounce) package frozen hash brown potatoes, thawed
• 1/2 cup butter, melted
• 1 can cream of chicken soup
• 1 (8-ounce) container sour cream
• 1 small onion, finely chopped
• 2 cups shredded cheddar cheese
• 1 teaspoon salt
• 1/2 teaspoon black pepper
• 2 cups cornflakes, crushed
• 1/4 cup butter, melted