All over Hawai'i you will find Kalua Pig anywhere Plate Lunch* is sold. In Hawai'i the best, most authentic stuff is smoked over banana leaves in a hot pit in the ground, but since you probably don't have a pit in the ground, or the banana leaves, this will likely have to do.
Slow Cooker Simple Hawaiian Kalua Pig:
Ingredients: a 4-6# pork butt roast, 1 1/2 Tablespoons Hawaiian salt (red preferred**), 1 Tablespoon Hickory Liquid Smoke.
Poke roast all over with fork, rub salt in, then rub in Liquid Smoke. Place in Slow Cooker on low for 6-8 hours (longer is ok). Turn once halfway through. When done, use two forks to shred, adding in drippings as needed to moisten.
*The classic combination, served from food trucks and general stores all over the islands is your choice entree, plus "2 scoops rice, and 1 scoop macaroni salad".
** Hawaiian Red Salt is sold in many Natural Food stores, because it contains minerals and micronutrients not found in standard table salt. Prepared from sea water, evaporated in salt pans lined with red volcanic clay, the resulting red salt is a traditional ingredient in Kalua Pig, adding color and flavor to the meat. If you can't find it, substitute coarse sea salt.