MISO: What is it?

Miso is a thick paste made from soybeans and grains that has been fermented and then aged for up to three years. It's a staple in Japan, where it's used to flavor soups, dipping sauces, meats, and dressings. There are hundreds of varieties of miso, and the Japanese match them to dishes with the same care that Americans match wines to meals. The darker kinds are saltier and more pungent, the lighter are sweeter and milder. Look for tubs of miso in the refrigerated section of Japanese food markets, health foods stores, or large supermarkets. It will keep in your refrigerator for many months.

From The Cook's Thesaurus