Slow cook a Boston butt pork roast by thinly slicing two large sweet onion and placing them into the slow cooker. Rinse the Boston butt roast and place it on top of the sliced onions. Add 1/4 cup of apple cider vinegar and one can of pineapple chunks. Dust the top of the roast with 1 tablespoons each of sea salt, celery salt, paprika, garlic powder, chili powder and basil. Cover and cook for 10 hours on low.
To make pulled pork in a slow cooker using a Boston butt pork roast, rub the roast with 1 tablespoon of olive oil and sprinkle with 2 tablespoons of salt and 2 tablespoons of pepper. Cook the roast in a large skillet to brown it on each side, about two minutes per side or until browned. Place the Boston Butt roast into the slow cooker with the fat side up. Cover and cook on high for one hour.
After cooking for one hour, reduce the temperature to low, and cook for six to seven hours or until the meat is fork tender. Remove the Boston butt pork roast from the slow cooker, and drain the liquid, reserving 1 cup.
Shred the pork roast and return it to the slow cooker with the reserved liquid to keep it moist.