Boil potatoes, peel skin once it's cold. chop them to cubes of equal size.
Heat oil in a pan or kadai. Shallow fry the potatoes till they are light golden and cooked.
Remove from oil and keep on a paper towel. Keep on serving plate.
Add salt, chat masala, cumin powder, red chilli powder, chopped onions, green chillies, coriander mint sauce, tamarind paste, beaten curd.
Mix them well. Garnish with finely chopped coriander leaves, onions and nylon sev. Serve.
You can make this chat by deep frying raw potatoes also. To make it crispier dip the diced cubes in ice cold water for 10 minutes.But in this chaat since I'm using boiled potatoes, I have shallow fried for 5 - 7 minutes till its little brown and crispy.