Nigella seeds are also known as black onion seeds, a misnomer as the seeds have nothing to do with onions. Nigella seeds are the dried, seed-like fruit of a small herb. The seeds are long and jet black with a matte finish. They closely resemble tiny chips of coal. Nigella seeds are sold whole and can be dry roasted and powdered at home. Nigella seeds are sometimes erroneously referred to as black cumin, an entirely different species.
Nigella seeds are used in India and the Middle East as a seasoning for vegetables, legumes, salads and breads. The black seeds taste like a combination of onions, black pepper and oregano, and have a bitterness to them like mustard seeds. It can be used as a pepper in recipes with pod fruit, vegetables, salads and poultry.