Add the water to the insert of a 6 quart or 8 quart Instant Pot.
Sprinkle in the salt (if using), and whisk to combine.
Add your steamer basket (*See notes for making without a steamer basket) to the insert, and add the broccoli to the steamer basket.
Secure the lid on the Instant Pot and move the valve to "sealing."
Set your pot on manual pressure and set the time for "0" minutes. Once the pot beeps, you'll know it has started to build pressure.
The pot will take approximately 8-13 minutes to come to pressure. Since our broccoli is cooking during the pressure building time, as soon as the Instant Pot switches over to the cook time, it will turn off because the time (0 minutes) has been completed.
Immediately flip the valve to "venting" to do a quick pressure release. Make sure you are not in the stream of steam, and use a long handled wooden spoon if needed.
Once the pin drops, indicating that the pressure has been released, go ahead and open your lid.
Lift the steamer basket out of the Instant pot and allow to drain in the sink or a large bowl for a few minutes.
Season to your taste, and serve immediately.