Remove the chicken pieces to a plate, then add the second tablespoon of oil and turn the heat to its highest setting. When the oil is really hot, add the peppers and onions and cook them in the hot oil, moving them around until their edges are slightly blackened. This should take about five minutes. Turn the heat down. Strip the coriander leaves from the stalks, reserving the leaves for later. Chop the coriander stalks finely and add these to the peppers and onions, along with the garlic, chillies, crushed spices, the chickpeas and rice, then give everything a good stir to distribute all the ingredients.