Start by cutting slicing the chicken breasts in half (butterfly style) so that you have thin filets.
Combine all of the marinade ingredients in a large bowl and add the chicken. Mix well until the chicken is fully coated in the marinade.
Remove the chicken with the marinade to a resealable plastic bag and let marinate in the refrigerator overnight or for at least three hours.
Preheat your grill and then add the chicken, cooking on each side for about 5-10 minutes, or until it reaches an internal temperature of about 165 degrees. Remove from the grill and let rest for approximately 5-10 additional minutes before cutting into smaller pieces.
Serve as tacos by adding the chicken to the tortillas and topping with cheese, mango salsa, and sour cream.