Bonito flakes, or katsuobushi, are made by smoking whole bonito or skipjack tuna fillets, then shaving them into delicate flakes that can be used as a meaty, umami-packed topping for all manner of Asian dishes. Because bonito flakes are used in large quantities to flavor the essential soup stock dashi, most brands sell them in overwhelmingly large quantities that can expire before the bag is used up. We prefer Yamaki's reasonably sized product; the package is just enough to make a batch of stock or sprinkle over rice, noodles, tofu, salads and more