Switch on the Instant Pot to Saute mode
Add in the oil.
Once hot add in the ginger and garlic and saute for a few seconds.
Now add the onion and again saute for 1 minute until slightly translucent.
Now add the grated butternut squash and a little salt.
Let it cook further for 1-2 minutes.
Add tomato puree/sauce, mixed herbs and give everything a quick mix.
Now add the pasta
Add water and adjust salt
Give it a quick mix.
Close the Instant pot lid.
Cancel the Saute mode and set it on pressure cooker mode , with sealing position on.
Cook it for the 3 minutes, on pressure cook mode. Check Notes above for timing.
Once the cooking time is over, let the pressure release naturally for 5 minutes.
After 5 minutes, switch the vent to venting.
Manual release all the pressure.
Once the pressure is released, open the instant pot lid.
If required adjust the consistency of the sauce by cooking it on Saute mode further.
Once done, switch off and serve hot.