Heat oven to 400°. Line a large baking pan with foil and lightly grease or spray with nonstick cooking spray.
Wash chicken thighs and trim excess fat and skin. Remove skin, if desired. Pat dry and sprinkle with salt and pepper.
Combine the melted butter with mustard, honey or syrup, and garlic powder in a shallow bowl. In another shallow bowl, combine the panko crumbs with shredded Parmesan, paprika, 3/4 teaspoon salt, 1/4 teaspoon pepper, and parsley.
Brush or rub the chicken thighs with the butter and mustard mixture then press all sides in the panko mixture to coat thoroughly. Place on prepared baking sheet. Bake for 40 to 50 minutes, or until juices run clear when chicken is pierced with a fork.