Vanilla, that most popular of scented-candle fragrances, is actually a fruit, produced by the orchid Vanilla planifolia. It takes three years for a plant to produce a flower, and the resulting pod must stay on the vine nine months before it can be harvested. (Meanwhile, as my mother would probably still love to remind me, we nonorchid beings can, in approximately the same amount of time, find a mate, get married, and have a baby.) With such a haute botanic background, no wonder the savory bean is so pricey—a single one cost me $6 at Whole Foods! Culinary historian and vanilla broker Patricia Rain examines the science, political economy, and social uses of this key cupcake ingredient in her book Vanilla: The Cultural History of the World’s Favorite Flavor and Fragrance. She includes recipes as well, so inspired readers can try the Aztec sex-enhancing drink chocolatl, vanilla ice cream à la Thomas Jefferson, or a ’50s banana-cream pie straight off the Nilla Wafers box. Rain proves vanilla’s far from plain at noon at the National Museum of Natural History’s Baird Auditorium, 10th Street and Constitution Avenue NW. Free. (202) 357-2700. (Hetty Lipscomb)