Everybody has one in their collection. You know--one of those old, spiral- or plastic-tooth-bound cookbooks sold to support a high school marching band, a church, or the local chapter of the Junior League. These recipe collections reflect, with unimpeachable authenticity, the dishes that define communities: chicken and dumplings, macaroni and cheese, chess pie. When the Southern Foodways Alliance began curating a cookbook, it was to these spiral-bound,...