You can do a lot more besides just the traditional Alaea red clay salt.
The traditional is simply Alaea salt, wrapped in banana leaves and cooked in a pit fueled by Kiawe wood (very similar to mesquite).
The pit being almost airtight infuses the smoke into the meat, very strong smoke flavor.
You just can't get this infusion of smoke through the banana leaves in a normal smoker, so ya gotta cheat.
I've been messing with both Kalua pork for awhile and here is what I've been doing for some very tasty Kalua pork.
I first marinate it overnight in,
Marinade
2C Orange juice
2C Pineapple juice
2C diced pineapple
1/2C Soy sauce
1/8C Fish sauce
3/4C minced ginger
3T minced garlic
4T salt
Since the salt is in the marinade and brines into the meat, it isn't like the traditional generous dusting directly on the meat before cooking.
I strain and keep all the pineapple, ginger and garlic with the butt, add a few splashes of liquid smoke (the cheat) around and atop the butt and then wrap in banana leaves and tie it up.
Then into the smoker till probe tender, generally around an IT of 205° +/-.
You can also do this in the oven or crockpot.
If you don't have twine you can set the wrapped butt in a dutch oven.
Banana leaves impart their own flavor to the meat, its a mild flavor, I don't know how to describe other than "Green".
Banana leaves can be found frozen at most Mexican markets or even ordered frozen from
Amazon.
If you use frozen, be sure to completely thaw before trying to use.