Light the grill. When it's hot, place a rolling pin, cutting board, bowl of flour, the melted butter and a brush near the grill. On a lightly floured cutting board, roll out a ball of dough to a 5-inch round. Gently slap the dough from one hand to the other to stretch it into a 7-to 8-inch oval. Stretch the oval into a traditional teardrop shape and immediately lay it on the hot grate. Grill the naan until the bottom is crusty and browned and the top is puffed and blistered, about 40 seconds. Brush with butter. Invert the naan and grill the other side until lightly browned, about 30 seconds longer. Grill the remaining naan the same way. Brush each naan with more butter as it comes off the grill and serve piping hot. Serve whole, or cut each naan into 3 wedges to serve the traditional way.