Preheat your oven to 350° Fahrenheit. This ensures that your casserole cooks evenly and thoroughly. While the oven is heating, take a moment to spray a 13×9 baking dish with non-stick cooking spray to prevent sticking.
In a large bowl, combine the frozen shredded hashbrowns, onion powder, dried thyme (if using), salt, pepper, and 1 cup of the shredded cheddar cheese. Stir until everything is well mixed. Make sure the hashbrowns are evenly coated with the spices and cheese for full flavor.
In a medium saucepan, add the butter and cream of chicken soup. Heat over medium-high heat, stirring until the butter melts. This mixture will add a creamy texture that is vital for the casserole.
Once the butter has melted, take the saucepan off the heat and stir in the sour cream. This step is crucial as it adds that luscious, creamy quality to your casserole.
Now, pour the creamy mixture over the hash brown mixture in the large bowl. Use a spatula to mix everything together until it’s well combined. You want every bite to be flavorful and creamy!
Transfer the combined mixture into the prepared baking dish. Spread it out evenly, ensuring that it fills the dish without leaving any gaps.
Top the casserole with the remaining 1 cup of shredded cheddar cheese. This will create a delicious cheesy crust as it bakes.
Place the baking dish in the oven and bake for 1 hour. Keep an eye on the casserole; it should be hot and bubbly when done. The cheese should be golden and slightly crispy.
Once baked, remove the casserole from the oven and let it cool for a few minutes before serving. This will help the casserole set up a bit, making it easier to cut into portions.
Serve immediately and enjoy the comforting flavors of Hashbrown Casserole with your loved ones!