Trim excess fat from the pork shoulder and cut it into large chunks.

In a small bowl, mix together the cumin, chili powder, garlic powder, onion powder, oregano, salt, and black pepper.

Rub the spice mixture all over the pork chunks.

Place the seasoned pork in the crockpot.

Pour the orange juice, lime juice, and chicken broth over the pork.

Cover and cook on low for 8 hours or until the pork is tender and easily shreds with a fork.

Remove the pork from the crockpot and shred it using two forks.

Return the shredded pork to the crockpot and mix it with the juices.

Serve with your choice of tortillas and toppings.