Creating the Chicken Cordon Bleu Casserole is simple and follows these easy steps:

1. Preheat Oven: Begin by preheating your oven to 350°F (175°C).
2. Combine Base Ingredients: In a large mixing bowl, combine the shredded chicken, diced ham, and half of the Swiss cheese.
3. Mix Sauce Ingredients: In a separate bowl, whisk together the cream of chicken soup, milk, Dijon mustard, garlic powder, onion powder, salt, and pepper until smooth.
4. Combine Mixtures: Add the sauce mixture to the chicken and ham, stirring well to coat all the ingredients evenly.
5. Prepare Casserole Dish: Grease a 9×13-inch baking dish with cooking spray or butter.
6. Layer Casserole: Pour the chicken and ham mixture into the prepared dish, spreading it evenly.
7. Add Cheese: Sprinkle the remaining Swiss cheese over the top of the mixture.
8. Top with Breadcrumbs: Evenly distribute the breadcrumbs over the cheese layer for a crunchy topping.
9. Bake: Place the casserole in the preheated oven and bake for 40-45 minutes or until bubbly and golden brown.
10. Cool: Once done, remove the casserole from the oven and let it cool for 10-15 minutes.
11. Garnish: Sprinkle with chopped parsley before serving for a fresh touch.

Following these instructions will lead you to create an amazing Chicken Cordon Bleu Casserole that is easy to enjoy and harder to forget.