Prep the base: Add the chopped onion and garlic to the bottom of your slow cooker.
Pour in the chicken broth.
Season the chicken: Place the chicken in the crockpot. Sprinkle evenly with taco seasoning, a pinch of salt, and black pepper.
Add the salsa: Pour the salsa over the chicken. Don’t stir—keeping the seasoning on top reduces clumping and helps flavor seep in.
Cook low and slow: Cover and cook on LOW for 4–6 hours or HIGH for 2.5–3.5 hours, until the chicken shreds easily with two forks.
Shred and finish: Remove the chicken to a cutting board, shred with two forks, then return it to the crockpot.
Stir in the lime juice. Taste and adjust salt, pepper, or more taco seasoning if needed.
Thicken if desired: If the mixture seems too saucy, remove the lid and let it cook on HIGH for 10–15 minutes to reduce. Or stir in a tablespoon of tomato paste.
Warm the tortillas: Heat a dry skillet over medium-high and warm tortillas 20–30 seconds per side until pliable and lightly charred.
Keep wrapped in a towel.
Assemble and serve: Fill tortillas with the shredded chicken and your favorite toppings. Serve with extra lime wedges and hot sauce.