1. Spray a large sheet of aluminum foil with olive oil spray.
2. Place potatoes in a mound in the center of the foil. Sprinkle on rosemary, salt and pepper and spray potatoes generously with olive oil spray.
3. Fold aluminum foil to create a packet -,- being careful to fold edges over so the potatoes will not slide out when you flip the packet.
4. Grill over medium heat for about 10 - 15 minutes, or until potatoes are tender - turning packet after about 7 minutes.