If language is the cultural DNA of high culture,

then food is the DNA of the illiterate masses. The fact that Thais eat hot chilies like fiends, but with very few varieties, and that they’re native to Mexico, with many varieties, would tell you something historical whether you read the book or not. Likewise with the potato, which has dozens of varieties in its native South American Andes, though more famous in Ireland, which has only one or two. There they suffered a potato blight and resulting famine so severe that they had to bring in more diverse DNA from the source with which to breed some disease resistance into the ‘Irish’ potato. One of the most typical traditional Tai dishes is kaow soi, found in Thailand, Laos, Burma, China, and sometimes Vietnam. There’s only one problem: it’s not the same dish everywhere. The dish in northern Thailand is properly kaow soi islam, a Burmese-style curry-like soup made with coconut milk and served over wheat noodles, not too surprising since northern Thailand was a Burmese colony for a couple hundred years. Real Tai kaow soi, like they still serve in Laos and Yunnan, China, is like northern Thai nam prik ong chili paste served in rice noodle soup, similar to northern Thai nam ngieow. Got that? Rice noodles themselves seem to have originated in Vietnam or southern China or both, given the two different names universally used for this product, pho and guaytieow, for which there are many variations in size, all taken quite seriously by connoisseurs. Then again, Thailand and Vietnam have different, but similar, products with the same name in nem and canh.