Cut two pieces of heavy-duty foil (about 18 in. x 12 in.); place a potato half on each. Spread cut side with butter. Sprinkle with garlic salt and pepper. Top each potato with another half. Fold foil over potatoes and seal tightly. Grill, covered, over medium-hot heat for 30 minutes or until tender, turning once. To serve, fluff potatoes with a fork and drizzle with honey.