Black cardamom, also known as hill cardamom, Bengal cardamom, greater cardamom, Indian cardamom, Nepal cardamom, winged cardamom, or brown cardamom, comes from either of two species in the family Zingiberaceae. Its seed pods have a strong camphor-like flavor, with a smoky character derived from the method of drying.
The pods are used as a spice, in a similar manner to the green Indian cardamom pods, but with a 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.
At least two distinct species of black cardamom occur: Amomum subulatum (also known as Nepal cardamom) and A. costatum. The pods of A. subulatum, used primarily in the cuisines of India and certain regional cuisines of Pakistan, are the smaller of the two, while the larger pods of A. costatum (Chinese: wiktionary:草果; pinyin: cǎoguǒ; Vietnamese: thảo quả) are used in Chinese cuisine, particularly that of Sichuan; and Vietnamese cuisine.
Black cardamom is often erroneously described as an inferior substitute for green cardamom by those unfamiliar with the spice; actually, it is just not as well suited for the sweet/hot dishes which typically include cardamom, and that are more commonly prepared outside the plant's native range. Black cardamom, by contrast, is better for hearty meat stews and similar dishes. Although the flavor differs from the smaller green cardamom, black cardamom is sometimes used by large-scale commercial bakers because of its low cost.
In China, the pods are used for jin-jin braised 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 thảo quả and used as an ingredient in the broth for the noodle soup called phở.