Place the chicken breasts in the bottom of a slow cooker.

In a mixing bowl, combine the chicken broth, lime juice, cilantro, garlic, cumin, chili powder, salt, black pepper, and red pepper flakes (if using). Stir well to combine.

Pour the mixture over the chicken in the slow cooker, ensuring the chicken is well coated.

Cover and cook on low for 6-8 hours or on high for 3-4 hours, until the chicken is cooked through and tender.

Once cooked, shred the chicken using two forks and stir it back into the sauce in the slow cooker.

Serve warm, garnished with additional cilantro and lime wedges if desired.