Mix the cooled butter, oil, garlic, Italian seasoning, paprika and salt together in a small bowl.
Wash the potatoes, place in the Instant Pot insert, then pour the stock over the potatoes and brush the seasoned butter over the potatoes.
Close the lid, turn the valve to sealing position, and set to high pressure / manual pressure for 5 minutes. Once done perform a quick pressure release.
Gently scoop out some of the cooking liquid and drizzle over the potatoes so they are coated in the mixture (but careful so they don't break), sprinkle with herbs, if desired, and serve.