In a large bag (I find Ziploc freezer bags work great), combine the ranch dressing mix and the panko crumbs.
Season the chicken and potato pieces with salt and pepper
Doing one piece of chicken at a time, place the meat in the bag and give it a great shake, ensuring coating sticks all over. Place on a parchment lined baking pan
Working with half the potatoes at a time, place them in the bag and also give them a good mix around in the bag to evenly coat. Place on the pan as well, laying them as flat as possible (not piling them on top of each other)
Bake for approximately 45 minutes. Check the chicken for doneness as well as the potatoes. If a fork goes in easily into the potatoes, and they are slightly golden on top, they are ready. You can use a thermometer to check the chicken if you are unsure.