Miso's meaty umami quality comes from a multi-step process of fermentation, which serves two functions: large molecules get broken down into small, readily-digestable ones, and the fermentation develops a lot of flavor. When it comes to miso, think beyond soups. You can improve an otherwise bland gravy or marinade with it, too. The first step in making miso: fermenting the fungus Aspergillus oryzae with steamed rice to create koji. It's like malting barley; the fungus introduces enzymes that break starches down into simple sugars. Next, koji is combined with cooked soybeans and salt in a second fermentation. The resulting miso is salty and packed with flavor.
Traditionally, miso paste is added to dashi stock, seaweed, cubes of tofu, and (sometimes) vegetables, near the end of cooking, to create miso soup.
White miso, made with rice, is mild. Yellow miso, made with barley, is a bit stronger, while red miso is especially salty and pungent.
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