First, boil the potatoes in a pressure cooker. Once cool to touch, peel and discard the skin. Cut into small cubes.
Take dahi and water in a large bowl. Whisk together till it smooth, keep it aside.
Heat the ghee in a kadai on medium heat. Once hot add cumin seeds and let them sizzle.
Then add ginger and green chillies. Saute for a minute.
Lower the heat to low, add red chilli powder, salt and crushed black pepper.
Now add boiled potatoes and roasted peanut powder. Mix well, so all the masala is coated with spices.
Add curd-water mixture and pinch of sugar. Stir well and let it come to a simmer. Let it simmer for 7-8 minutes. Do stir in between.
Mash a few pieces of potatoes if you like, this will help to thicken the gravy
And again simmer for 1-2 minutes or till the gravy becomes thick.
Mix well and turn off the flame.
Serve with vrat ki roti or same ke chawal.