Harissa can be three things - a fiery hot red chilli paste, a stew of green capsicums, tomatoes and onion with spices or a thick soup of lamb and wheat. The main spices used remain pretty constant - caraway, corainder and cumin. There are also a number of dried harissa mixes onthe market to which you add oil or water to make into a paste - look for them in speciality food shops.
