Preheat the oven to 350°F and lightly grease a 9x13-inch baking dish to prevent sticking.
In a large mixing bowl, combine the sour cream, cream of chicken soup, 6 tablespoons melted butter, salt, pepper, dried onion, garlic powder, and paprika. Stir until the mixture is smooth and fully blended.
Add the thawed hash browns and shredded cheddar cheese. Gently mix until the potatoes are evenly coated with the creamy mixture.
Transfer the mixture into the prepared baking dish and spread it out evenly so it cooks uniformly.
Place the cornflakes in a zip-top bag and lightly crush them. Pour in the remaining melted butter and toss until the crumbs are coated.
Sprinkle the buttered cornflake topping evenly over the casserole. Add a small pinch of salt if desired.
Bake uncovered for 40 to 50 minutes, until the casserole is heated through and the topping is golden and crisp. Let sit for a few minutes before serving.