Pour the soup into a medium bowl. Fill the empty can with milk, and add to the bowl along with the parsley and onion powder. Mix well. Place bread crumbs in a shallow dish or bowl; dip chicken thighs in soup mixture, then in crumbs, and place coated pieces in a lightly greased 9x13 inch baking dish.
Drizzle with melted butter and bake in preheated oven until chicken is nicely browned and cooked through (juices run clear), about 45 minutes.
Meanwhile, place remaining soup mixture in a small saucepan and whisk in cornstarch. Cook over medium heat, stirring occasionally, until mixture comes to a boil; reduce heat and simmer for a minute or two until sauce thickens. Use this as a sauce when chicken is done.
