Combine potatoes, coriander leaves, chaat masala, chili powder, garam masala, salt in a bowl and mix well.
Refrigerate for half an hour.
Divide the mixture into equal portions and shape each portion into a nice round tikki.
Mix water with the all purpose flour to make a smooth paste.
Dip the prepared tikkis in the paste.
Coat with breadcrumbs on all sides by rolling it in breadcrumbs filled plate.
Heat oil in a non-stick tava (griddle) on a medium flame and shallow fry the tikkis, till both sides are golden brown in colour.
Serve hot with tomato ketchup or green chutney.