Saffron is the most expensive spice in the world. It's derived from the dried stigmas of the saffron crocus and has a deep auburn colour and sweet flavour. The stigmas can only be picked by hand and it takes 250,000 stigmas to make just half a kilo of saffron, hence its high price. Fortunately, a little saffron goes a long way.
Saffron can be bought whole in threads or strands (stigmas) or in powdered form. Spanish and Kashmiri saffron are reputed to be among the best-quality.
Saffron gives a distinctive aroma and flavour and a yellow colour to Spanish paella and Italian risotto and is also a classic ingredient in the French fish soup, Bouillabaisse. Crush the stigmas and soak in water before use.