Traditionally, the natto is added with soy sauce or Japanese mustard (generally sold in department stores in boxed natto, using Japanese light soy sauce and yellow mustard), stirred until the silky material appears, placed on white rice, is for natto rice. Some people also mix natto with raw eggs, onions, scallions, radishes, firewood and other ingredients. Natto and sugar are sometimes mixed in Hokkaido and the northeast. There is also a creative way to eat mayonnaise. If you add the sauce without stirring, it will cause too much water, and the stickiness will decrease. Onion and mustard will suppress the pungent smell of natto ammonia. People who are not used to eating natto think it is rotten boiled soybeans.