Thirty minutes before cooking, remove the lamb chops from the fridge and place on a rimmed baking sheet.
Evenly distribute the salt and rosemary leaves on both sides of the lamb chops.
Add the olive oil and butter into the Instant Pot. Set the sauté feature to 12 minutes.
Brown the lamb chops, one minute per side in batches of three.
Once all lamb chops have been browned, add the tomato paste and shallot. Cook for 1-2 minutes, until the tomato paste is browned. Stir frequently.
Deglaze with the beef stock.
Add lamb chops and their juices to the Instant Pot. Cover and cook on high pressure for 2 minutes.
Once cooked, release pressure immediately.
Place the lamb chops on top of creamed cauliflower, top with pan sauce and pickled red onions.