Wash potatoes, leave the skin on, and cut in half lengthwise. Mix remaining ingredients in a 9x13 roasting pan or other roasting dish that will hold all the potato halves in a single layer. Coat the potatoes by turning them in the oil/spice mixture, leaving the potatoes cut side down in the pan. The potatoes should be well coated on all sides with the oil/spice mixture. Place in the preheated oven and roast until the potatoes develop a nice brown crust and pierce easily with a fork, about 30-40 minutes. Serve with meat or fish.