Mix the seasoning. In a small bowl, stir together salt, pepper, smoked paprika, garlic powder, onion powder, cumin, chili powder, and cayenne if using.

Prep the pork. Pat the pork shoulder dry with paper towels. Rub it all over with avocado oil, then coat thoroughly with the seasoning blend. Press the spices in so they stick.

Layer the slow cooker. Add the sliced onion to the bottom of the slow cooker if using. In a measuring cup, whisk broth, apple cider vinegar, tomato paste, and mustard. Pour this mixture around (not over) the pork so the rub stays on the meat.

Add bay leaves and cook. Tuck in the bay leaves. Cover and cook on Low for 8–10 hours or High for 5–6 hours, until the pork is very tender and shreds easily with two forks.

Shred the pork. Transfer the pork to a large bowl. Remove any large fatty pieces. Shred with two forks into bite-size strands.

Reduce the juices (optional but recommended). Skim excess fat from the cooking liquid. Pour the liquid into a saucepan and simmer for 8–10 minutes to concentrate flavor. Alternatively, leave it in the slow cooker on High with the lid off for 20–30 minutes.

Toss and taste. Return the shredded pork to the slow cooker or a large bowl and toss with enough reduced cooking liquid to keep it juicy. Taste and adjust salt, pepper, or vinegar. A small splash of vinegar at the end brightens it up.

Serve your way. Try it over cauliflower rice with a squeeze of lime, pile it into lettuce wraps with slaw and pickles, or enjoy it with roasted veggies. Add a drizzle of no-sugar-added barbecue sauce if you like.