Slice the onions and the greens as finely as possible. Slit the green chilly. (If you are looking for a spicy version, then slit the green chillies also finely. Alternately you can avoid it and increase the quantity of pepper ).
Take oil in a pan. I normally use my mud pot for this. Add the onion, green chilly, and the greens and fry well till the greens are wilted.
Add the rice water and allow it to cook completely.
To the coconut milk add the cornflour and keep ready.
Once the soup starts boiling and the leaves are cooked well, add the coconut milk - corn flour mix and stir continuously till the soup thickens. Do not boil after adding coconut milk, as it will thin out.
Add salt, pepper powder and sugar to taste .
Switch off and serve.