Under no circumstances use green peppers for this dish. They are merely unripe red peppers, and will give you chronic wind.
Cook the peppers directly over the flame. Turn them occasionally until the skin is completely black and blistered. Do not be faint-hearted; cook them on the highest heat, char them until you think they are overdone, and then blacken them some more. Remove to a bowl, clingfilm the top, and leave the peppers to steam and cool for 30 minutes.
Peel quickly under running water, using the col