Creating Comforting Chicken Cordon Bleu Casserole is straightforward if you follow these steps:

1. Preheat Oven: Preheat your oven to 350°F (175°C).
2. Prepare Baking Dish: Grease a 9×13-inch casserole dish with cooking spray or butter.
3. Mix Chicken and Ham: In a large bowl, combine the shredded chicken and diced ham.
4. Add Cheese: Stir in 1 ½ cups of the shredded Swiss cheese into the chicken and ham mixture.
5. Create Sauce: In a separate bowl, whisk together the sour cream, chicken broth, Dijon mustard, garlic powder, onion powder, salt, and black pepper.
6. Combine Mixtures: Pour the sauce over the chicken and ham mixture, stirring until well combined.
7. Transfer to Baking Dish: Spread the mixture evenly into the prepared casserole dish.
8. Top with Breadcrumbs: Sprinkle the remaining ½ cup of Swiss cheese over the top, followed by the breadcrumbs.
9. Bake: Place the casserole in the preheated oven and bake for 30-35 minutes or until the top is golden brown and bubbly.
10. Garnish: Once done, remove from the oven and let it cool for a few minutes. Garnish with fresh parsley before serving.

Following these steps will guide you in creating a comforting casserole that is both delicious and satisfying.