Thaw the potatoes overnight in the refrigerator, or spread them out on a baking sheet and warm in a 200°F oven for about 20 minutes, until fully thawed.

Set your oven to preheat at 350°F.

In a large bowl, mix together the sour cream, cream of chicken soup, 6 tablespoons of melted butter, salt, pepper, and dried onion until well combined.

Stir in the thawed potatoes and shredded cheese, mixing until everything is evenly coated. Spread the mixture in an even layer in a 9×13-inch baking dish.

Place the cornflakes in a large zip-top bag and gently crush them using your hands or a rolling pin.

Pour the remaining 4 tablespoons of melted butter over the crushed cornflakes and toss to coat. Evenly sprinkle the cornflake mixture over the potatoes in the baking dish.

Bake, uncovered, at 350°F for 40 to 50 minutes, until hot and bubbly.

Serve alongside baked ham, oven-roasted turkey, or flank steak for a delicious meal.