To cook a pork roast in the a slow cooker, first, trim any excess fat from the roast. Rub the meat with olive oil and sprinkle with salt and pepper. Cut the roast in half.
Any time you have a piece of meat or poultry that is larger than 2 pounds, it's best to cut it into smaller portions so that it will cook evenly and help the center of the meat reach the recommended temperatures in less time.
Brown the roast halves in hot oil in a large skillet for 2 minutes on each side or until lightly browned. You're not thoroughly cooking the meat at this point, just browning the outside—this just helps to get the outside of the meat brown.
Place the roast halves in a lightly greased 6-qt. slow cooker, fat sides up. Because the slow cooker generates steam that doesn’t escape, there will be a good bit of liquid at the end of cooking, so there's no need to add any extra liquid to the meat.
Cover and cook on HIGH for 1 hour. Reduce the heat to LOW, and cook for 6 to 7 hours or until meat is tender and slices easily. Starting out on HIGH heat for an hour allows the slow cooker to heat up faster, and the heat to penetrate the cut of meat and eradicate any bacteria.
Remove the cooked pork, reserving the liquid, and slice the meat. Add 1 cup of the reserved liquid to the pork to moisten., and serve.