What is Annatto?

Annatto — A paste produced from achiote seeds, which are ground and used as a spice in parts of Latin America. Annatto is more important as a colouring agent than as a spice. It's used to make a bright orange-yellow dye that's produced commercially and used to colour butter, margarine, cheese (such as Cheshire and Lancashire) and smoked fish such as mackerel and kippers.