Preheat the oven to 350.
Lightly spray a 9X13" baking dish with cooking spray. Set aside.
Butterfly chicken breasts to create a pocket in each.
In a medium bowl combine bread crumbs and melted butter. Stir to mix.
Sprinkle about 1/4 of the bread crumb mixture in prepared dish.
Lay the cut chicken breasts in prepared dish.
Open each breast an place slice of ham and slice of cheese. Close fold.
Sprinkle remaining bread crumb mixture over the top.
Bake for 40-45 minutes until internal temperature 165.
Start sauce whrn chicken is nearly complete.
In a medium pan, over medium heat, melt butter.
Whisk in flour, stirring constantly, for 2 minutes to make a roux.
Gradually add the milk while whisking constantly.
Add in the onion powder and garlic powder.
Whisk mixture constantly for sauce thickens.
Remove from heat and add Worcestershire sauce, Dijon and Parmesan cheese.
Stir until the cheese melts.
Reduce heat.
Plate each chicken breast serving and drizzle with warm sauce.