Wash and clean spinach. Chop into large pieces together with stalk. Peel and cut the potato and onion into medium size pieces.
Heat oil. Saute onion with ½ teaspoon salt.
Add the potatoes with 500 ml water and boil for 10 minutes or until soft.
Once the potatoes are cooked, add the chopped spinach and cook for one minute. By cooking the spinach only briefly, the bright green colour is retained.
Strain the cooked vegetables. Preserve liquid. Puree vegetables until smooth in the blender.
Add strained liquid, spice powder, salt and pepper to the pureed vegetables and bring to boil.