Saffron is the world’s most expensive spice by weight. Produced from the stigmas of saffron crocuses that are harvested by hand and dried, saffron comes to us in short, extremely slender threads (and thread saffron is superior to powdered). Its color, a burnished red, is as prized as its fragrance, which I’m sad to say I cannot describe, and its flavor, which is somewhat bitter and, once you know it, unmistakable for anything else. (It’s the iconic flavor of bouillabaisse and its cousin the Riviera Fish Soup, page 92-94.) Given the price of saffron, it’s good that a little goes a very long way — and it will go longer if before you add it to anything, you crush the threads between your fingertips. Depending on the recipe, you might also want to soften the saffron in a little warm water or broth first (and, of course, add the liquid to your dish).