Natto

Natto is soybeans fermented with Bacillus subtilis until they develop a sticky, stringy texture and a pungent aroma that is an acquired taste for many outside Japan, where it is a classic breakfast food. It is traditionally stirred vigorously with chopsticks until the strands turn foamy, then mixed with the small packets of soy sauce and karashi mustard that come with it, and spooned over a bowl of hot rice. Beyond the classic rice bowl, natto is folded into okonomiyaki batter, tossed with chopped scallions and a raw egg yolk, stirred into miso soup, or used as a topping for cold tofu; its sticky texture clings well to noodles too. The stickiness is part of the appeal for fans and the main hurdle for newcomers, so starting with strong mix-ins like mustard and soy sauce is the usual way in.

Natto is sold refrigerated or frozen in small containers, usually in Asian grocery stores; check for a fresh date and thaw frozen packs in the refrigerator overnight rather than on the counter. A cup, 175 grams, provides 211 calories with 19.4 grams of protein, 39 percent DV, and 5.4 grams of fiber, 19 percent DV, along with 48 percent DV of iron and only 7 milligrams of sodium, making it a low-sodium way to add a fermented soy component to a rice-and-vegetable meal. Once opened, use it within a day or two, and keep in mind fermentation continues in the fridge, so flavor and smell intensify the longer it sits.