Creating Million Dollar Chicken Casserole can be straightforward when you follow these clear steps:

1. Preheat Oven: Preheat your oven to 350°F (175°C).
2. Prepare Dish: Grease a 9×13 inch baking dish with non-stick spray or butter.
3. Mix Ingredients: In a large bowl, combine the shredded chicken, sour cream, cream of chicken soup, shredded cheddar cheese, mixed vegetables, milk, garlic powder, onion powder, salt, and black pepper. Stir until well combined.
4. Transfer to Baking Dish: Pour the chicken mixture into the prepared baking dish and spread it evenly.
5. Prepare Topping: In a separate bowl, mix the crushed cornflakes with melted butter. Stir until all flakes are coated.
6. Add Topping: Scatter the buttery cornflakes evenly over the chicken mixture in the baking dish.
7. Bake: Place the casserole in the preheated oven and bake for 45 minutes or until the top is golden brown and bubbly.
8. Cool Slightly: Once finished, remove from the oven and let it sit for about 5 minutes before serving. This allows the casserole to set and makes it easier to serve.
9. Garnish (Optional): Feel free to garnish with fresh herbs, like parsley or chives, to enhance presentation.

Following these steps will lead you to an incredible Million Dollar Chicken Casserole!