Stir the garlic, soup, cumin and chile powder in a 4-quart slow cooker.
Add the chicken and turn to coat.
Cover and cook on LOW for 7 to 8 hours or HIGH for 4 to 5 hours until the chicken is fork-tender. Remove the chicken to a cutting board. Using 2 forks, shred the chicken.
Return the chicken to the cooker.
Stir in the picante sauce.
Serve the chicken mixture in the tortillas topped with lettuce and cilantro.