Sour star fruit

Known to Malay-speakers as belimbing buluh, this small green, elongated fruit is a relative of the more famous yellow star fruit but it is extremely sour and is used predominantly in cooking. Sour star fruit, when added in small quantities, imparts a tartness to the dish. It is sometimes also known as sour finger carambola. If sour star fruit is unavailable, replace with segments of lime.