Cambridge, Massachusetts, chef Chris Schlesinger, and food writer John Willoughby, both big fans of real barbecue, came up with the model for this unusual relish for their terrific book, The Thrill of the Grill (1990, William Morrow). We’ve tinkered a bit with the original version to tailor it to smoked food. The texture is best when you chop the pickles and vegetables not much larger than the corn kernels.