Miso is usually available in Asian grocery stores and health food stores. Some major grocery store chains with expanded organic foods sections, such as Wegmans, also sell miso. It is typically sold in a plastic tub.
Even though miso is best when refrigerated, it can also be purchased online through websites such as Amazon.com. Miso is a thick, salty, tangy paste made from fermented soybeans. It is most commonly used in Japanese-style miso soup and other Asian dishes, but it can also add flavor to salad dressings, marinades and vegetable dishes. White or yellow miso generally has a milder flavor than the brown or barley varieties.