Boil the potatoes fully, peel and cut them into small pieces/mashed.
Heat some oil in a pan.
Splutter mustard seeds, black gram and fenugreeks.
Add the ginger and green chillies
Add finely cut onions and fry until the onions turn brown/transparent.
Add tomato pieces into the mixture and fry for some time.
Add the potatoes and salt and fry.
Add curd into the whole mixture.
:- Don`t boil after adding the curd.
Finally, add some curry leaves.
:- Serve hot with Chapathi/Roti or Rice.