You can cook the potatoes in your preferred way. Peel and cube them. I steamed my potatoes in Instant Pot for 5 minutes using my steamer basket and naturally release the pressure. I then peeled and cubed them.
In a mixer jar, grind the green chilies, ginger, and the 1 tbsp of cilantro coarsely - no need to add any water. Set it aside.
In a pan or kadai, heat 1 tbsp of oil. When the oil is hot, add the mustard seeds, cumin seeds, sesame seeds, and hing.
After about 30 seconds, add the curry leaves and when the mustard seeds splutter, add the boiled and cubed potatoes, salt, turmeric powder, and the ground paste.
Mix well and cook for about 7 to 10 minutes over low heat until the potatoes get a slight crust. Make sure to stir in between the cooking process.
Turn off the heat. Add the lemon juice and garnish it with cilantro and serve warm with dal and rice or thepla.
Notes
You can use any potato variety for this dish. Just make sure to cook them soft and firm so that it holds the shape.
As the potatoes are pre-cooked, after tempering, you can cook them for 3 to 4 minutes. I went ahead and roasted them over low heat for 10 minutes.
The original recipe doesn't call for grinding cilantro along with ginger and green chilies. But as we like the refreshing flavor, I went ahead and added cilantro while making the paste.
As always, adjust the salt and spices according to your preference.