Ingredients:
- 4 cups cooked and chopped chicken
- 1/2 pound deli ham, chopped
- 1/2 pound Swiss cheese, shredded
- 1/2 cup all-purpose flour
- 1/2 cup (1 stick) unsalted butter
- 2 cups whole milk
- 1 tablespoon Dijon mustard
- 1 tablespoon Worcestershire sauce
- 1/2 teaspoon garlic powder
- Salt and pepper, to taste
- 2 cups panko bread crumbs
- 1/2 cup grated Parmesan cheese
- 1/4 cup chopped fresh parsley

Instructions:
- Preheat the oven to 375°F (190°C). Grease a 9×13 inch casserole dish with cooking spray.
- In a large mixing bowl, combine the cooked chicken, chopped ham, and shredded Swiss cheese. Spread the mixture evenly in the prepared casserole dish.
- In a medium saucepan, melt the butter over medium heat.
- Whisk in the flour, and continue whisking until the mixture turns golden brown.
- Gradually add the milk, whisking constantly until the mixture is smooth.
- Add the Dijon mustard, Worcestershire sauce, garlic powder, salt, and pepper, and whisk until well combined.
- Pour the sauce over the chicken mixture in the casserole dish, making sure the mixture is evenly coated.
- In a separate mixing bowl, combine the panko bread crumbs, grated Parmesan cheese, and chopped fresh parsley. Sprinkle the mixture evenly over the chicken mixture.
- Bake the casserole in the preheated oven for 25-30 minutes, or until the bread crumbs are golden brown and the cheese is melted and bubbly.
- Allow the casserole to cool for a few minutes before serving.
Enjoy your delicious chicken cordon bleu casserole!