Heat olive oil in an oven-proof skillet over medium-high heat.
Sprinkle and massage a generous amount of kosher salt and pepper all over the pork. Sear the pork on all sides until deep brown.
Transfer the skillet to the oven. Roast for 30 to 40 minutes, or until a thermometer reads 140 degrees. Turn over once halfway through roasting. Remove the pork from the skillet and wrap in tin foil. Allow the pork to rest in the foil for 10 minutes.
Meanwhile, make the sauce. Using the same skillet, place it over medium-high heat on the stove top. Deglaze with the bourbon, scraping up the brown bits from the bottom of the pan. Whisk in the soy sauce, ketchup and brown sugar. Bring the sauce to a boil. Reduce the heat to low and cook for 2 minutes.
Remove the pork from the tin foil. Whisk any drippings that have collected in the tin foil into the bourbon-barbecue sauce.