Add 1 teaspoon oil in cooking pan and heat it.
Add half teaspoon cumin seeds and cook it until its colour change to light brown
Add 2 finely chopped green chillies in it and cook it until it raw flavour vanishes.
Add 6-7 curry leaves in it and cook for 1 minute.
Now turn off the gas and let the tadka cool it.
Put 1 cup whisked curd in a bowl.
add 2 boiled mashed potatoes in it.
Add rock salt (sendha namak) on it.
Now add tadka on top of it.
Mix all ingredients and garnish it with chopped coriander leaves.