Place pork butt in the slow cooker fat side up. Cover with Hawaiian rock salt, and drizzle liquid smoke over meat.
I pour just enough water into the slow cooker so that it just covers the bottom of the pan, less than a quarter-inch of water. Make sure you don't pour the water on the meat, just around it on the sides.
Set slow cooker to 8 hours on low setting.
Shred pork using 2 forks.
Cut cabbage into large square pieces. Boil for 5-7 minutes until tender.
Line serving dish with boiled cabbage and top with shredded kalua pork.
Recipe by Bebe Love Okazu at https://bebeloveokazu.com/2010/03/30/kalua-pork/