Put the olive oil in the Instant Pot and turn it on to the Saute setting. While the oil heats, pats the tenderloins dry and sprinkle both sides generously with sea salt and pepper. When the oil it hot (it should run very quickly across the bottom of the pot when you tilt it, and look thinner/more runny than cold oil). Use a pair of long tongs to carefully place each tenderloin in the hot oil and allow it to sear for 5-7 minutes, or until it is lightly browned. Flip the meat and allow the second side to cook until it’s equally browned. Remove the tenderloins and set them aside on a plate. Take one cup of the chicken stock and pour it into the Instant Pot while whisking to remove any stuck bits of meat. Place the meat back in the pot, put the lid on with the valve turned to sealing, and set it to cook on high pressure for 4 minutes. While the meat is cooking, make the sauce by whisking together the 1/2 cup of the chicken stock, wine, dijon mustard, cornstarch, and garlic. Set it aside until the meat is ready. When it has finished cooking, do a quick release by turning the valve on the lid to release. Once the pressure indicator has gone down, remove the lid and once again take out the meat. Put the pot back on the sear setting and pour the sauce in. Allow it to bubble and cook, stirring occasionally, until it has thickened, about 3-5 minutes. Slice the pork tenderloins, then pour the sauce over them. Serve with rice or mashed potatoes.