Combine the first 5 ingredients (through salt) in a 4- to 6-quart slow cooker. Add the pork, and turn to coat.
Cook pork, covered, on high for 4–5 hours or on low for 7–8 hours, or until the meat is tender and pulls apart easily.
Preheat oven to 350° 20 minutes before serving. Stack the tortillas, and wrap in foil. Bake for 15 minutes or until warm.
Shred the pork with 2 forks, and stir meat into the cooking liquid. Serve shredded pork with warm tortillas, cilantro, sour cream, lime, and extra salsa.
adapted from Real Simple