Funeral Potatoes

Defrost the Potatoes - Thaw the potatoes in the refrigerator overnight or in the microwave on the defrost setting until no longer icy. Drain off any water.
Heat the Oven - Set the oven rack to the center position. Heat the oven to 350ºF (177ºC).
Make the Sauce - In a large bowl, whisk together the sour cream, cream of chicken soup, 5 tablespoons of melted butter, dried minced onion, ¾ teaspoon salt, black pepper, and nutmeg if using.
Add the Potatoes and Cheese - Add the defrosted potatoes, shredded cheese, and chives. Stir to combine.
Prepare the Topping - In a small bowl, combine 3 tablespoons melted butter and ¼ teaspoon of salt. Add the corn flakes to a medium bowl. If you prefer smaller cereal pieces, lightly crush them to the desired size. Drizzle the butter mixture over the corn flakes and stir to coat.
Assemble the Casserole - Evenly spread the potato mixture in a 13x9-inch baking dish. Sprinkle the corn flake mixture on top to cover the surface.
Bake - Bake until hot and the topping is golden brown and crispy, 45 to 55 minutes. If the corn flakes are browning too quickly, around 30 minutes, loosely cover the baking dish with foil.
To Serve - If desired, garnish with chives right before serving. Serve while still hot.