In a very large skillet set to medium high heat. When the pan is hot add the cooking oil. Add the pork loin to the skillet and brown on all sides, no need to cook through, the slow cooker will do that.
Transfer the pork loin to the slow cooker.
Add the onion, barbecue sauce, apples, vinegar and black pepper.
Cover and cook on low for 7 hours without opening the lid during the cooking time. Slice and serve, enjoy!
These nutritional values are approximate. If you require a special diet, please use your own calculations. Values below are for 1/8 of recipe.