Remove pork from refrigerator 1-2 hours prior to cooking and bring to room temperature. If the pork is still cold or partially frozen cooking time will be longer.
Preheat smoker to 250°F.
Generously salt all sides of pork with Hawaiian Alaea salt just prior to cooking.
Place pork in smoker and add wood chips according to smoker instructions. I use hickory wood chips but have also had good results with Applewood.
After 3 hours, remove pork from the smoker. Wrap in banana leaves and 2 layers of foil to seal in the moisture. Place the pork back in smoker. Check temperature after 3 hours, and every half hour after that, until it reaches 190-200°F.
Cooking times can vary anywhere from 6.5 to 9 hours, depending on size of the pork shoulder.
After pork has reached temperature, remove it from smoker and let it rest for at least 10 minutes. Remove pork from foil and banana leaves and shred, saving some of the juices.
If not using immediately, place shredded pork in a container with reserved juices and refrigerate. To reheat the pork, spread over a large baking sheet and heat in a 350°F oven until hot.
While the pork is smoking, make the sauce. In a medium saucepan heat the coconut oil and add the onion, sautéing until translucent, about 4 minutes.
Add the tomato paste, ginger, and garlic and cook, stirring well, for 1 minute.
Add the water, guava paste, spiced rum, rice vinegar, soy sauce, lime juice, honey, chipotle in adobo, and fish sauce and stir well until well mixed and the guava paste is fully melted.
Bring to a boil, then simmer for about 20 minutes, stirring once in a while, until slightly reduced and thickened. Taste and add more chipotle in adobo if a spicier sauce is desired.
Let cool, then transfer to a glass jar or bowl with an airtight lid. The sauce tastes best after letting cool in the refrigerator at least 4 hours, but overnight is best for all the flavors to come together.
The sauce can be used cold or reheated, and lasts up to 2 weeks refrigerated or 3 months frozen.
Cut the Hawaiian rolls in half. Toast. Cut the pickle strips in half. Place a few on the bottom half of the bun.
Top with about 1/4 cup of kalua pork, add a tablespoon or two of the guava rum BBQ sauce, and the top half of the bun. Repeat until you have as many sliders as you would like to make.