Add the potato cubes to the instant pot along with garlic cloves, salt, and water, and stir well.
Put the lid on the instant pot and secure it well. Set the valve to the sealing position.Press PRESSURE COOK and set the timer for 12 minutes on high pressure. The instant pot will take some time to build the pressure and start the timer.
Once the timer goes off, let the pressure release naturally for 10 minutes. Release the remaining pressure by moving the valve to the venting position.Once the pressure is released, open the lid.
Mash the potatoes using a potato masher. There is no need to drain the water.
Add olive oil, butter, sour cream, and cream cheese to the pot and mash until the potatoes are smooth and creamy. Check for salt and add more if needed.
Transfer the potatoes to the serving bowl. Keep a tab of butter on top and garnish with chopped herbs and red pepper flakes. Serve warm.