Trim excess fat from the pork shoulder, leaving some for flavor. Cut the meat into 3-4 inch chunks to ensure even cooking.

Season the pork chunks generously with salt and pepper on all sides.

Heat vegetable oil in a large skillet over medium-high heat. Working in batches, sear the pork pieces until browned on all sides, about 2-3 minutes per side. Transfer the browned meat to your slow cooker.

In the same skillet, reduce heat to medium and add the chopped onion. Sauté until translucent, about 3-4 minutes. Add minced garlic and cook for another 30 seconds until fragrant.

In a mixing bowl, combine chicken broth, ketchup, apple cider vinegar, brown sugar, Worcestershire sauce, smoked paprika, chili powder, cumin, mustard powder, garlic powder, onion powder, cayenne pepper, salt, and black pepper. Whisk until well combined.

Pour the sauce mixture over the sautéed onions and garlic in the skillet. Bring to a simmer for 1-2 minutes, stirring to scrape up any browned bits from the bottom of the pan.

Pour the entire sauce mixture over the pork in the slow cooker. Cover and cook on low for 8 hours or on high for 5 hours, until the pork is fork-tender and easily shreds.

Once done, remove the pork from the slow cooker and transfer to a large bowl or cutting board, leaving the sauce behind.

Using two forks, shred the pork into bite-sized pieces, removing any large pieces of fat.

If the sauce in the slow cooker seems too thin, transfer it to a saucepan and simmer over medium heat until reduced and slightly thickened, about 10-15 minutes.

Return the shredded pork to the slow cooker and mix with the sauce. Keep warm until ready to serve.

For serving, lightly toast the hamburger buns and pile the shredded BBQ pork onto the bottom halves. Top with coleslaw if desired, and cover with the top buns.