Put the broth or water, potatoes, onions, garlic, salt, pepper and red pepper flakes, if using, in the Instant Pot.Close the lid and make sure the valve is set to Sealing. Push the Pressure Cook (or Manual) button and adjust time using the + and - buttons to get to 6 minutes. When it beeps that it's done, flip the valve from Sealing to Venting for a quick release and when the pin drops …