Mix 2 thinly sliced onions, 1 chopped potato, 2 chopped green chilies, a little chopped coriander, 1 tsp cumin, 1 tsp chili powder, ½ tsp turmeric, salt, and 1 cup gram flour (besan). Add a little water to make a thick batter. Heat oil in a pan, drop small portions of the mixture into the hot oil, and fry until golden brown and crispy on both sides. Remove onto paper towel and serve hot with ketchup.