Set the Instant Pot to Sauté mode and wait until the indicator shows HOT. Add the olive oil. When the oil is fully heated, add the potatoes, placing them skin side up first.
Leave the potatoes to cook for about 2 minutes, until the surface turns brown and crispy. Turn the potatoes over and repeat. Then add the garlic, herbs, chicken broth, lemon juice, salt, black pepper, cayenne pepper (if using), and Parmesan cheese.
Cover the pot, select Manual, and set it to High Pressure for 8 minutes. When it beeps, perform a Quick Release. Once the valve drops, carefully remove the lid. Set the Instant Pot to Sauté mode, add the heavy whipping cream, stir well, and reduce the sauce slightly. Serve the Instant Pot potatoes warm.