1. Chop potatoes into 1 inch cubes. Place in a medium sized pot, add enough water to cover, cover with lid and bring to a boil over high heat. Once boiling remove lid, drop heat and simmer for 12 - 15 minutes or until the potatoes are fork tender.
3. Heat 1 tablespoon of olive oil in a 10 or 12 inch skillet over medium high heat. Cook the pork medallions for 2 - 3 minutes on each side, ensuring an internal temperature of 145ºF. Once finished, remove pork from pan and allow it to rest while you make the gravy.
5. Continue to cook until it has reduced by half, then add the butter and swirl to melt. Add the flour and whisk until it reaches a paste like consistency. Cook 1 minute longer, then add the stock. Whisk constantly until the gravy has thickened and comes to a boil.