Place all barbacoa ingredients in crockpot on high for 4 hours or low for 8 hours.
Shred beef with two forks in the crockpot.
Spread out a single layer of meat on rimmed baking sheet and broil in the oven for 5 minutes (or in the air fryer at 400) to get the meat slightly crispy.
While the meat is in the oven, warm the corn tortillas in the microwave.
Serve on corn tortillas with onion, radish, cilantro, lime wedges, and salsa.