Press SAUTE on Instant Pot. Add oil to the pot. Once hot, add mustard seeds, let them splutter.
Next, add green chili, curry leaves, and asafoetida (hing). Saute for a few seconds.
Add chopped onion and saute till onions turn light brown.
Next, add diced butternut squash, turmeric powder, salt, water, and mix well. Deglaze the pot, make sure to scrape off any food particles if sticking to the pot.
Close the lid on the pot. Set the pot to MANUAL/PRESSURE COOK (High Pressure) and set the timer to 2 MINUTES.
When the instant pot beeps, Do a QUICK RELEASE (QR).
Remove lid away from you, add coconut cumin ground mixture, mix well and cook for 1-2 minutes. Adjust seasonings if required.
Butternut Squash Poriyal is ready, serve with hot rice, chapatis, roti and parathas.