1tspprepared yellow mustard(if you like Dijon mustard you can use that instead)
1/2tspsalt, and then to taste
1/4tspfreshly ground black pepper
Preheat oven to 375 degrees. Place diced chicken in an even layer in a buttered 11x7 baking dish, set aside. To prepare sauce: in a mixing bowl (I just mixed it all in the liquid measuring cup after measuring the milk out), whisk together milk, lemon juice, prepared yellow mustard, onion powder, 1/2 tsp dried parsley, dried thyme, salt, 1/4 tsp pepper and garlic powder.
Melt butter in a saucepan over medium heat, once melted whisk in flour and cook stirring constantly for 1 minute. While whisking, pour in milk mixture, then cook stirring constantly until mixture just begins to gently boil and has thickened. Remove from heat, stir in sour cream.
Pour mixture evenly over chicken and use a spatula to spread into an even layer. Sprinkle ham over sauce then sprinkle grated Swiss and Parmesan cheese evenly over ham layer. In a small mixing bowl, whisk together Panko bread crumbs, 1/2 tsp dried parsley, 1/8 tsp pepper then pour in Extra Virgin Olive Oil and toss bread crumb mixture to evenly coat. Sprinkle bread crumb mixture evenly over cheese layer. Bake casserole in preheated oven for 30 minutes until golden brown on top. Serve warm.
*I used left over spiral sliced ham and I diced it into chunks then tossed them in the food processor and chopped them for about 10 seconds to get really small pieces. Basically any good quality ham would work as long as it's honey or smoked ham.