In a large bowl, combine apple cider, brown sugar, apple cider vinegar, soy sauce, Dijon mustard, cinnamon, garlic powder, onion powder, and black pepper. Stir until well mixed.

Set aside about 1 cup of the marinade for later use.

Place the pork shoulder in a slow cooker.

Pour the marinade over the pork, ensuring it is well coated.

Cover and cook on low for 8 hours or until the pork is tender and easily shredded.

Check occasionally to ensure there is enough liquid; add water if necessary.

Once cooked, remove the pork from the slow cooker and place it on a cutting board.

Shred the pork using two forks, discarding any large pieces of fat.

Return the shredded pork to the slow cooker and mix with the remaining marinade.

Serve the pulled pork on burger buns topped with coleslaw, if desired.