Combine rub ingredients in a small bowl. Remove any twine from the pork. Rub the spice mixture all over the pork, using your hands. I suggest placing pork on a baking sheet to catch any fallout.
In a slow cooker, add the Worcestershire sauce, chili powder, chicken broth, garlic, ground cumin, liquid smoke, and brown sugar. Stir until combined. Add the pork into the slow cooker and cover. Set on low and cook for 10 hours.
When the pork is about ready, combine the slaw ingredients and refrigerate until needed.
When the pork is done, take it out of the slow cooker and place it on a cutting board. Using two forks, shred it. Depending on your piece of meat, you may need to remove larger fatty pieces. I like to keep some of the smaller fatty pieces as they make the sandwiches taste even better. Place the shredded pork on a plate, bowl, or in a storage container. Spoon some of the leftover cooking liquid onto the pork and toss. It's up to you how much/how little you use. If you're not going to top your sandwiches with BBQ sauce, I suggest adding more of the liquid.
If desired, toast the insides of the buns. To do this, I add some butter into a skillet on medium-high heat and toast the inside of each bun half for a few minutes.
Fill the buns with BBQ sauce, slaw, and the pulled pork. Enjoy!