"Taking it to the next level" has become a rather trite cliché over the last few years, but when it comes to Roxy's Gourmet Grilled Cheese, it really does apply. This Beantown-area food truck serves up inventive takes on the classic comfort food, adding ingredients like guacamole, braised short ribs, roasted summer vegetables, grilled and caramelized onions, and, of course, bacon. They also serve handcut truffle fries and roasted tomato soup, the latter only in cold weather, as well as lemonade and water. That's not a lot of options, but after the first few bites you'll realize anything else would be unnecessary.