Season the pork shoulder/butt generously with salt and pepper on all sides and place it in the slow cooker. Whisk together the garlic, vinegar and soy sauce and pour it into the slow cooker.
Cover and set the slow cooker for 10 hours on low (if you are in a rush, you can also try 6 hours on high) or until the pork is fork tender and coming apart. If possible, rotate the pork shoulder once during cooking (this helps, but is not necessary).
Once cooked, carefully transfer the pork to a cutting board. Shred the pork using two forks, and discard any fat. Stir in about 1/4 cup of the liquid to keep the pork moist.
Discard bay leaf. Transfer the liquid remaining in the slow cooker into a sauce pan, and stir in the honey and molasses, along with some cayenne pepper. Let it come to a boil, then then lower heat to a simmer, and cook for about 5 minutes. If you have an immersion blender, blend the sauce together to puree the sauce into a smoother consistency if you wish. Adjust seasoning if necessary. Remove from heat.
Assemble the sandwiches by placing a layer of cabbage on one half of a bun, top with pulled pork, some sauce, sriracha, jalapeno and cilantro. Top with the other half of the bun and enjoy immediately.