First make up the filling.Heat oil in a kadai.Add in mustard and cumin seeds to it and let it splatter.
Add in green chilli,ginger,curry leaves and mix well.Throw in onions and sauté for 3 min.
Add in red chilli powder,turmeric powder and mix well.Now add in the boiled mashed potatoes and mix everything together.
Garnish with coriander leaves and lemon juice and mix well.
Let this cool down..Divide this into equal portions and form smalls out of it.
Heat oil for deep frying.
Now make the batter by mixing gram flour,rice flour,ginger garlic paste,salt,baking powder,turmeric powder,chilli powder along with water and form a smooth paste out of it.
Dip the potato ball in the batter and deep fry in heated oil till golden on both sides.
Serve hot with coconut chutney.