Set the instant pot into the sauté mode and add the cooking oil.
Add the cumin seeds and allow them to splutter and brown a bit. If using Paprika or Kashmiri red chili powder, add it to the oil now.
Now add the tomato-spice puree and give a good mix.
Allow the mixture to come to a boil (approximately 2-3 minutes).
Now add potatoes and mix well.
If you like a hot curry, add ½ teaspoon of chili powder at this point, and mix well.
Cover and seal the lid. Set the mode to pressure cook and add 3 minutes in the timer.
After the beep, wait for 5 minutes more before quick releasing pressure.
Open the lid and give a good stir.
Now add 1-2 cups of water, and bring the mixture to a boil in the sauté mode. Adjust the consistency as per your preference. I like a runny potato curry than a thick one, so I avoid crushing some potatoes while cooking.
Once the curry boils, switch off the instant pot and add chopped cilantro and adjust salt if necessary.
Serve hot with poori, rice or naan.