With the Instant pot on sauté mode. Add oil and onions and sauté for a minute. Add tomato paste, Thai curry paste, and water. Mix well and de-glaze the pot.
Make sure nothing is stuck at the bottom. Now add butternut squash cubes, salt, curry powder, and soy sauce. Mix everything well.
Cover with locking lid, press the manual/pressure cook and set the timer for 5 minutes under high pressure. Once done let the pressure release naturally for 5 minutes then quick release.
Carefully open the instant pot, add finely chopped kale and coconut milk. Mix everything well.