The pods are used as a spice, in a manner similar to the green cardamom pods, but those have a drastically different flavor. Unlike green cardamom, this spice is rarely used in sweet dishes. Its smoky flavor and aroma derive from traditional methods of drying over open flames.
There are at least two distinct species of black cardamom: ''Amomum subulatum'' and ''Amomum costatum'' or ''A. tsao-ko''. The pods of ''A. subulatum,'' used primarily in the , are the smaller of the two, while the larger pods of ''A. costatum'' are used in Chinese cuisine, particularly that of ; and Vietnamese cuisine.
In India, black cardamom seeds are often an important component of the Indian spice mixture garam masala. Black cardamom is also commonly used in savory dal and rice dishes.
In China, the pods are used for long- meat dishes, particularly in the cuisine of the central-western province of Sichuan.
The pods are also often used in Vietnam, where they are called ''th?o qu?'' and used as an ingredient in the broth for the noodle soup called ''ph?''.
Black cardamom pods can be used in soups, chowders, casseroles, and marinades for smoky flavor, much in the way bacon is used.
Black cardamom is often erroneously described as an inferior substitute for green cardamom by those who are unfamiliar with the spice. Although the flavor differs from the more common green cardamom, black cardamom is sometimes used by large-scale commercial bakers because of its relative cheapness.
In Chinese medicine, tsao-ko is used to treat stomach disorders and malaria.
Packages warn not to eat the product uncooked or as a snack food.