Chop the veg - Peel the butternut squash and dice it into 1/2 inch cubes. Chop the broccoli into small pieces as well. You don't want the pieces to disappear into the cheesy sauce, but you don't want a bite of just squash or broccoli either.
Pressure cook - Set the Instant Pot to cook for 7 minutes, high pressure.
Mix in the cheese - When the cook time is done, do a quick release and turn off the Instant Pot. Add the cheese and the half-and-half, and stir to combine. Cover and let sit for three minutes to allow the cheese to melt and the sauce to thicken.