Set a wire rack or steamer trivet inside the bowl of a 6-quart or larger Instant Pot. Place the potatoes on top of the rack in a single layer, as best as possible. Pour in the water. Lock the lid and set the valve to seal. Pressure cook on high for 12 minutes for larger potatoes, and 8 minutes for baby potatoes. Do a quick release to remove the pressure and then carefully open the lid.
Remove the potatoes and set aside. Discard the water and then dry the inner bowl with a clean kitchen towel. Set the machine to sauté and once hot, add the oil and butter, along with the cooked potatoes. Cook, stirring often, until the potatoes have begun to brown, about 3 minutes. Season with salt, pepper, granulated garlic, granulated onion, cayenne pepper and rosemary. Turn off the machine and transfer to a serving platter. Garnish with chives, parsley and Parmesan cheese.