A comforting and flavorful casserole featuring layers of mashed potatoes, seasoned chicken, and melted cheese.
Preheat your oven to 350°F (175°C).
Ensure the oven is fully preheated for even cooking.
Butter a 9x13 inch baking dish to prevent sticking.
Use softened butter for easier application.
Spread the mashed potatoes evenly across the bottom of the baking dish, creating a slight edge around the sides.
Warm the mashed potatoes slightly for easier spreading.
In a mixing bowl, combine the shredded chicken, sour cream, dry mustard, garlic powder, and black pepper until well mixed.
Taste the mixture and adjust seasoning as needed.
Spread the chicken mixture evenly over the mashed potatoes in the baking dish.
Ensure an even layer for consistent baking.
Sprinkle the shredded cheddar cheese evenly over the top of the chicken mixture.
Distribute the cheese evenly for a uniform crust.
Bake the casserole in the preheated oven for 45 minutes, or until the cheese is melted and bubbly.
Check halfway through to ensure even cooking.
Let the casserole rest for 10 minutes before serving.
Resting allows the layers to set for easier serving.