Niboshi are small fish—most commonly Japanese anchovies—that have been boiled in salt water and then dried. In Japanese cooking, they are used primarily to make dashi broth, where they produce a deep, assertive umami that is distinctly different from the more refined character of kombu or katsuobushi. Unlike many dried fish traditions around the world, where the fish itself is eaten directly, niboshi exist mainly to release their flavor into water. When simmered, they produce one of the most satisfying and distinctly Japanese broths in the cuisine. That bold character is what makes them the foundation of miso soup in ...