Preheat oven to 500°F. In a small frying pan melt butter and garlic. Let stand a few minutes; butter should still be melted. Whisk in Dijon mustard, and set aside. In a pie plate, mix the panko, Parmesan, and parsley flakes. Coat chicken in the Dijon mixture and dip one side (the side skin was on) in the panko mixture. Place chicken crumb side up in a foil lined 10 X 15 inch baking pan. Bake 15 min. or until crumbs are brown and chicken is done. To test, pierce with a fork. Juices should run clear.
