Layer the chicken: Place the chicken breasts in the bottom of your slow cooker in a single layer if possible.
Add seasoning and salsa: Sprinkle the taco seasoning evenly over the chicken. Pour the salsa on top. If your salsa is extra thick, add a splash (1/4–1/2 cup) of broth so there’s enough moisture.
Cook low and slow: Cover and cook on Low for 4–5 hours or High for 2.5–3.5 hours, until the chicken is tender and easily shreds with two forks.
Shred the chicken: Transfer the cooked chicken to a cutting board and shred with two forks.
Return the meat to the crockpot and toss with the salsa juices.
Finish and taste: Stir in lime juice if using. Taste and adjust seasoning with a pinch of salt, more salsa, or extra taco seasoning as needed.
Serve: Spoon into tortillas, over rice or cauliflower rice, on salads, or use it for nachos, enchiladas, or burrito bowls.