Assemble potatoes, carrots, onion, and garlic on a parchment-lined baking sheet.
Drizzle with olive oil and sprinkle with rosemary, and half the black pepper and salt. Roll around and rub to coat everything evenly.
Sprinkle remaining salt and pepper on either side of each chicken thigh.
Arrange chicken thighs skin-side up on top of the vegetables.
Roast at 425˚F (220˚C) for about 40-50 minutes or until the chicken reads 165˚F (73˚C) internal temperature and skin is crispy.
