Preheat oven to 400 degrees F. Place a large wire rack over an 18 by 13-inch baking sheet, spray wire rack with non-stick cooking spray.
Pour Panko into a shallow mixing bowl. Drizzle with olive oil and toss and rub with fingertips to evenly moisten.
Add paprika, thyme, garlic powder, cayenne pepper and season with salt and pepper to taste then toss.
In a separate shallow mixing bowl, whisk together egg whites, salt and pepper until slightly frothy.
Working with one pieces of chicken at a time, dip both sides of chicken in egg white then transfer to Panko mixture and dredge both sides in mixture while pressing crumbs to adhere, sprinkle some crumbs over top as well and press.
Transfer to prepared wire rack spacing evenly apart.
Bake in preheated oven until golden brown and cooked through (center of thickest portion should register 165ºF on an instant read thermometer), about 50 minutes. Serve warm.
If your oven generally browns more than average and you find the Panko coating is getting darker than you'd like, you can drape a sheet of foil over the chicken when needed and continue to bake through.
This method will work for boneless thighs or boneless chicken breasts too. Cook time will be about half but as always test to 165 degrees F in center for doneness.