If you have leftover chicken skip this step. Heavily season your chicken breasts. Quickly sear both sides of the breasts in a cast iron skillet and then place skillet in a 350°F oven. Cook until almost done or to 140°F. Remove to plate and let rest 5-10 minutes.

Mix 2 Tbsp melted butter and the Panko breadcrumbs in a bowl. Mix well and set aside. Add 4 Tbsp butter and shallots to the skillet and cook until soft. Add garlic and cook for 30 seconds. Whisk in flour and cook for 2 minutes. Add white wine and cook off liquid, 1-2 minutes. Next whisk in chicken broth, milk, heavy cream, mustard, cayenne pepper, and black pepper and bring to a simmer. Cook about 5-10 minutes until it thickens some. Remove from heat and stir in 1 cup of the cheese mixture.

Spray Pam on a small baking dish. I used a 8” x 11” dish. Layer bottom of dish with 1/3 of chicken, then 1/2 the ham, then 1/4 cup of cheese mixture. Repeat process for the second layer. Layer the remaining chicken on top. Pour in sauce to cover dish contents. Spread remaining cheese mixture, about a cup, on top of sauce.

Place casserole on a preheated 350°F oven. Cook for 30 minutes, until casserole is bubbling and the breadcrumbs are browned. If you want you can use your broiler at the end to get a nice browned, crispy top. Serve and enjoy. Rice makes a good side for this casserole with all the great sauce.