For the casserole:
- 1 whole cooked chicken, bones removed, meat diced or shredded (rotisserie chicken is excellent, should have 5-6 cups)
- 1/2 pound very thinly sliced deli-style honey ham, rough chopped
- 1/4 pound thin sliced baby Swiss cheese
For the sauce:
- 4 tablespoons butter
- 4 tablespoons flour
- 3 1/4 cups milk
- 2 tablespoons fresh squeezed lemon juice
- 1 tablespoon dijon mustard
- 1 1/2 teaspoon salt
- 1/2 teaspoon smoked paprika
- 1/4 teaspoon pepper
For the topping:
- 6 tablespoons butter
- 1 1/2 cups panko bread crumbs
- 1 1/2 teaspoons crushed dried parsley
- salt and pepper to taste
- Preheat oven to 350 F. Butter a 9- x 13-inch baking dish. Set aside.
- Put cooked shredded or diced chicken on the bottom of the baking dish. Rough chop the ham and scatter it over the top of the chicken.
- Lay the Swiss cheese on top of the ham.
- To make the sauce: Melt the butter in a large sauce pot over medium heat. When butter is melted, quickly stir in the flour to form a smooth roux. Do not brown! Once the roux is smooth and bubbly, slowly pour in the cold milk while stirring briskly to make a smooth sauce. Cook over medium heat, stirring constantly until the sauce thickens. Stir in the lemon juice, Dijon mustard, salt, smoked paprika and white pepper. Bring sauce just back to a low boil and turn off heat. Pour sauce evenly over the casserole, being certain to get some of the sauce around the edges of the pan.
- To make the topping: Melt the butter in the microwave in a medium sized microwaveable bowl. Heat it for 30 seconds at a time and stop once it’s melted. Take the bowl out of the microwave and stir in the panko bread crumbs, seasoning salt and crushed dried parsley.
- Sprinkle over the top of the casserole.
- Bake casserole uncovered for 45 minutes until hot and bubbly throughout and topping has turned a light golden brown.
- Remove from oven and allow to cool for 5-10 minutes prior to serving.