True or green cardamom (or when bleached, white cardamom) comes from the species Elettaria cardamomum and is distributed from India to Malaysia. What is often referred to as white cardamon is actually Siam cardamom.
Cardamom has a strong, unique taste, with an intensely aromatic, resinous fragrance. Black cardamom has a distinctly more smoky, though not bitter, aroma, with a coolness some consider similar to mint.
Green cardamom is one of the most expensive spices by weight but little is needed to impart flavor. It is best stored in the pod, as exposed or ground seeds quickly lose their flavor. Grinding the pods and seeds together lowers both the quality and the price. For recipes requiring whole cardamom pods, a generally accepted equivalent is 10 pods equals 1 1⁄2 teaspoons of ground cardamom.