The trick to this dish is not overcooking the aubergines. They need to be just cooked through so that they’re fairly soft, but still holding their shape. If you take them too ?far you won’t get the contrast in texture between them and the silky smooth peas. ?a cautionary note about harissa; the level of heat varies greatly depending on where you buy it (the supermarket stuff tends to be more gentle, whereas the tunisian variety in tubes is pretty fiery stuff). With that in mind, add it gradually and to taste.