Mashed boiled potatoes until smooth and set aside.
Heal oil in a pan add garlic and mustard. Fry for few seconds then all the remaining ingredients of tempering. Give it a stir and cook for 1 minute.
Now, stir in chopped onions, mix well and remove from heat.
Add the mashed potatoes, sugar, and lemon juice to the tempering. Mix well and make 15 small balls. Keep in the fridge to cool for 10 minutes to chill or until needed.
Meanwhile, make the batter for coating by mixing all ingredients for coating in a bowl. Make a smooth and thick batter of dropping consistency.
Heat about 2 inches oil in a non-stick wok or pot. Dip each potato ball in the chickpea flour batter. Lift it carefully with wooden spatula. Slowly slide the ball into hot oil without denting it.
Fry 4-5 balls in a batch. Spoon oil over the ball but do not stir until firm. Then flip the ball and cook evenly until golden.
Remove from oil to a paper towel. Serve hot with any chutney or sauce.