"[K]oji [is] the Japanese manifestation of qu, also traditionally a mixed culture but today typically known as a single a strain of fungus, '. Before I started growing koji, I would never have believed it possible to fall in love with a mold. ...Koji itself is not generally eaten as a food (although it is delicious). Koji is the first step toward many elaborately processed foods and beverages. ...try it at least once using a starter culture so you can experience the unique aroma of fresh growing koji, because recognizing that unique smell is the most straightforward way you have to gauge whether you have the right mold growing if you try starting koji spontaneously using corn husks."