Add curd and buttermilk in a mixing bowl and mix well.peel and mashed the boiled potatoes.

Heat oil in a wok,now add chopped onion and saute it.

Add all spices and roaste for 2 minutes and add mashed potatoes,mix well.

Now add buttermilk and curd mixture and boiled it.

Cook on low flame for 10 minutes.

Now switch off the flame and add chopped green coriander,green chillies.

Ready to eat yummy dahi aloo.serve with roti.