Add the chicken, garlic, olive oil, and spices in a large bowl or zip-seal bag.
Place in fridge and let marinate for at least 15-30 minutes or up to 24 hours.
Remove chicken from marinade and discard marinade.
Place chicken on a grill or pan heated to medium-high heat.
Let chicken cook until it is no longer pink on the inside, about 9-10 minutes per side (or until it has reached an internal temperature of 165 degrees F).
To Make Cilantro Sauce
Place all the ingredients in the food processor and blend for 1 minute or until creamy.
To Assemble
Layer lettuce wraps with chicken, tomatoes, onion, and avocado.
Drizzle with cilantro sauce or your favorite taco sauce