Boston chef and cookbook writer Jasper White knows a lot about soft-shell clams. ''I grew up on the Jersey shore,'' White told us, ''and in those days, we had steamers coming out our ears. At local bars, peanuts cost money, but steamers were free!'' At home, White's mother taught him to soak clams in cornmeal-laced water to purge them of their sandy sediment. Some folks still swear by this method—but working as a chef in New England, White learned that adding cornmeal to the soaking water doesn't really work. Instead, he soaks his soft-shell clams in big bowls of cold salted water, gently lifting them from one bowl to the other, changing and swishing the water and repeating the process until it's almost clear of sediment. But to clean that last bit of grit, just swish steamed clams in the broth they're served with.