In a large zipper-top bag, combine all of the spices, and then add the lime juice and 1 tablespoon of the oil. (This will create more of a wet rub than a liquidy marinade.) Mix well, add the chicken, seal the bag, and then shake the chicken around to evenly coat in the spice mixture. Refrigerate for at least an hour or two, if possible, and up to 6-8 hours.
In a 12-inch skillet (cast iron works well) heated over medium-high, sauté the peppers and onions in the remaining tablespoon of oil until crisp-tender, about 6-7 minutes. (If you prefer the onions to be cooked down more than the peppers, sauté them for 2-3 minutes before adding the peppers.) Remove to a plate.
In the same skillet, cook the chicken over medium-high heat for 3-5 minutes or until no longer pink. Precise cooking time will depend on how thinly the chicken is sliced. Return the pepper mixture to the pan for just long enough to heat through, another minute or so.
Spoon the chicken mixture down the center of the warm tortillas. Top with cheese, salsa, guacamole, etc., and then fold over and enjoy.