Liberally salt and pepper the chicken. Add olive oil to a large cast iron skillet over medium high heat. Deeply sear chicken on all sides, 3-5 minutes per side. Remove chicken and set aside.
Move all potatoes to one side of pan and add the chicken back to the pan (it's okay if it overlaps, it's already browned). Squeeze juice of one lemon over the chicken, and add half the lemon cut side down to the pan to roast (optional). Put pan in oven and roast until an internal thermometer in the chicken reaches 165, 30-45 minutes.
Remove the chicken and top with remaining parsley, and more juice from roasted lemon. Allow chicken to rest before serving.
Recipe by The Two Bananas at https://thetwobananas.com/one-pan-roasted-chicken/