Wash nicely and peel potatoes.
Cut into 1" cubes. You may cut into small pieces. Keep potato cubes soaked in water till you prepare fenugreek leaves.
Finely chop fenugreek leaves, use a food processor or chopper if you have.
Heat oil in a kadhai or heavy bottomed pan. If using mustard oil, heat oil till starts to give slight smoke. Switch off the gas and let the oil cool a bit.
Add cumin seeds in hot oil, once the seeds crackle add ginger and green chilli.
Add cubed potatoes and sauté for 2-3 minutes.
Add chopped fenugreek leaves and salt as per taste. Mix well cover and cook the veggie.
Keep on stirring in between and keep the flame to medium low so that subzi doesn't burn at bottom. Cook till potatoes are soft and tender. You can use a fork to check cooked potatoes.
Switch off the gas and serve hot with chapatis/parathas or dal rice.