Coconut oil (this gives aviyal a good aroma, so do not substitute) Wash and cut all the vegetables lengthwise into 2" pieces(stick shape). Cook the vegetables by adding little water ( I prefer to add water now and then and I make sure I do not add more water and end up draining the water with lots of nutrition from the veggies). Also one should be careful not to overcook the vegetables: they should remain crisp.(There are some vegetables which cook very fast and some which take a long time. Keep adding the vegetables according to the cooking time, the longer cooking vegetables first and the quicker ones last). Once the vegetables are cooked, grind coconut, cumin, green chillies and add to the cooked veggies. Add the beaten curd and let stay in heat for a minute and remove. Finally, tamper the curry leaves with coconut oil I make it little watery so as to eat with adai. Enjoy the aviyal with you adai. Aviyal can also be used in the main course along with rice and sambar.