Preheat oven to 325°F.
Line a large roasting pan with banana leaves: place one leaf in the pan, then place a second leaf on top in the opposite direction to form a cross.
Place the pork shoulder on top of the banana leaves. Using a small knife, puncture the meat all over.
Sprinkle pork with Hawaiian salt and rub it firmly into all sides.
Brush 1 teaspoon liquid smoke over the pork, coating all sides.
Wrap the banana leaves up and around the pork to fully enclose it. Turn the pork over so the loose ends are tucked underneath. Secure with butcher’s twine if desired.
Pour 1 cup water into the bottom of the roasting pan and add the remaining 1 teaspoon liquid smoke. Cover the pan tightly with aluminum foil.
Roast for 4–6 hours, or until the pork is fork tender and shreds easily.
Remove from the oven and let rest, covered, for 30–60 minutes.
Unwrap the pork and transfer to a large pan or cutting board. Shred with two forks, discarding excess fat or gristle.
Taste and season with additional salt if needed. Moisten the shredded meat with some of the cooking liquid for extra flavor and juiciness.
Serve warm with rice, cabbage, or your favorite Hawaiian-style sides.