Spring is here, and for many that means the beginning of outdoor cookouts with that old American standby, the hamburger. Rainouts? Not to worry. There are plenty of restaurants, diners and taverns out there to fill the void on those less-than-nice spring days, with their own takes on this classic sandwich. Whether you like it plain, with cheese, bacon, mushrooms, or just about anything else, there’s an abundance of choices out there to satisfy any burger lover’s palate.