Marinate the chicken for at least 24 hours (Best: 48 hrs) with black pepper, olive oil, garlic, parsley, lemon juice, sumac, and sprinkle liberally with salt.
Make sure the marinade and spices are rubbed in and cover the chicken evenly. Breast side down and cover with plastic wrap. Store it in fridge until you roast it.
(If you marinate the chicken for 2 days, flip it over once until you roast it.)
Pre-heat the oven to 420F. Roast the chicken skin-side up for 25 minutes.
When it starts to brown, turn it down to 400F for another 20-25 minutes.
Turn the oven temperature up to 420F for the last 5 minutes until the meat is cooked through and the juice runs clean.
Serve with baked root vegetables, squash, or potatoes.