Heat the oil in a large frying pan. Simmer the onion till soft and the creen curry. Lower the heat and stir for a minute, adding some water to prevent from burning. Add the coconut milk slowly while stirring constantly till the sauce is smooth.
Add the eggplants and courgettes. Bring to a boil and lower the heat immediately. Cover and let it simmer very gently for 10 – 15 minutes. Add the cauliflower and let simmer uncovered for 5-10 more minutes.
Add the lemon juice, decorate with the basil or coriander and serve with jasmin rice and a crispy green salad.