Mix smoked paprika, brown sugar, garlic powder, onion powder, chili powder, salt, and black pepper in a small bowl. Rub the spice mixture all over the pork shoulder, pressing it into the meat.
Place the seasoned pork shoulder in the slow cooker, fat side up.
In a bowl, whisk together bbq sauce, apple cider vinegar, chicken broth, and worcestershire sauce. Pour the mixture evenly over the pork.
Cover and cook on low for 8 to 10 hours or on high for 4 to 5 hours, until the pork is completely fork-tender and pulls apart easily.
Transfer the pork to a large cutting board. Shred the meat using two forks, discarding any large pieces of fat.
Return the shredded pork to the slow cooker and toss it in the cooking juices. Let it sit on warm for 10 to 15 minutes to soak up all the flavor before serving.