Close lid and turn valve to sealing, then set your Instant Pot to manual high pressure for 20 minutes. (Hit the manual button, use the + - buttons to bring the time to 20 minutes, then hit the manual button again to start.)
When the Instant Pot beeps, let it naturally release for 15-20 minutes before turning the valve to release the remaining pressure.
Open the pot and remove vegetable scraps with a slotted spoon into a fine-mesh strainer placed over a large bowl.
Use the back of your spoon to press the liquid out from the veggies, then discard scraps.
Pour the remaining broth through the fine-mesh strainer to catch any more stray pieces.
You'll end up with over two quarts of delicious vegetable broth -- made from scraps you would previously have discarded!
It's OK to throw the veggie scraps in frozen, but don't use cabbage, broccoli, or other cruciferous vegetables because they will make the broth bitter.
Instant Pot Vegetable Broth -- From Veggie Scraps from Mashup Mom: