Add one teaspoon lemon juice and a pinch of salt to the ginger strips and keep in the refrigerator till use.
Heat sufficient oil in a kadai till medium hot.
Add potato pieces and deep fry till crisp and golden. Drain and place on an absorbent paper.
Transfer the potatoes into a big bowl. Add onions, salt, chaat masala, red chilli powder, cumin powder, green chilies, coriander leaves and the remaining lemon juice and mix well.
To serve transfer the mixture into a serving bowl, garnish with ginger strips and serve immediately.