Applying heat to lettuce goes against everything I’ve ever been taught about the proper treatment of delicate leafy greens. Scared off by visions of slimy, wilted iceberg, the mere concept of tossing a few defenseless heads of romaine onto a roaring grill sounds like some nauseating joke. Heat and its transformative properties have the last laugh though; screaming-hot grates merely char the surface, imparting a bold new world of flavor in their wake while leaving the refreshingly crisp heart int...