Pungent and peppery, nigella seeds are tiny, jet-black seeds that come from a flowering plant of the same name. Also called kalonji or black onion seeds, nigella seeds are used in Indian and Middle Eastern cooking to flavor vegetables, beans, and breads. Nigella seeds have an angular shape—almost triangular—with sharp edges. Sometimes mistakenly labeled as black cumin or black caraway, the nigella seed has its own mildly bitter, musty flavor. Nigella seeds are available at Middle Eastern and Indian markets, and at some specialty stores.