Natto
Natto is a traditional Japanese food made from whole soybeans that have been fermented with Bacillus subtilis var. natto. It is often served as a breakfast food with rice. It is served with karashi mustard, soy or tare sauce, and sometimes spring onion. Within Japan, natto is most popular in the eastern regions, including Kantō, Tōhoku, and Hokkaido.
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