Tahini or sesame paste can be substituted for miso if only a small amount is needed for a recipe. However, the exact flavor of miso can not be replicated.
Miso is a paste made of boiled or crushed soybeans. A culture made of beans, barley, wheat or rice is then added to the paste. The mixture is fermented for as long as three years before it is used. Miso is used in soups and ramen. The paste is also part of dressings, sauces and marinades. Miso has 32 grams of protein, 15 grams of fiber and 17 grams of sugar per serving.