The tikkis need not be fried for long. They should just be brown and crisp on both sides and soft inside. Flip only when one side is done. Turning and tossing them frequently can break them. They should turn crisp and brown on both sides and yet be soft inside. It took me 2-3 minutes to cook each side. If you use a large tava, you can make multiple patties in one go. The potato patties can be baked in the oven or air fried instead of shallow frying. You can also fry them in oil.