Mix the fajita spice mix in a bowl and set aside. Reserve one tablespoon of the spice mix for the vegetables.
Add the thinly sliced chicken and salt and pepper in a second bowl. Add the fajita spice mix and mix to combine.
Add the washed long-grain rice, cold water, and salt to a saucepan. Bring to a boil, reduce heat to low, cover, and cook for 12 minutes. Turn off the heat and leave the lid on for 4-5 minutes. Remove the lid and fluff with a fork or spatula. Add the drained black beans and chopped coriander. Mix to combine and set aside.
Place a large, high-rimmed pan or pot over medium-high heat. Add 1 tbsp (20ml) of avocado oil, and once hot, add the onion and bell pepper mix. Sauté for 6-8 minutes, mixing regularly. Add the reserved 1 tbsp of fajita spice mix and cook for 1 minute. Remove and set aside.
Place the same pan back over medium-high heat. Add the remaining 1 tbsp (20ml) of avocado oil and sear the chicken for 4-5 minutes, or until cooked through and golden. Add the oregano, onion, and bell pepper mix to the pan and cook for 1 minute. Remove from heat.
For the guacamole, mash the avocado, leaving it slightly coarse. Add all of the remaining ingredients and mix well. Check and adjust seasoning and acidity, and add the avocado oil (optional).
Slightly warm the tortillas and spread each tortilla with 1/5 of the guacamole. Add the black bean coriander rice and top with the chicken fajita mix. Drizzle over salsa or sauce of choice and wrap tightly, tucking in the sides of the tortilla.
(OPTIONAL) — Toast in a dry pan, oven, or air fryer until golden and toasted. This can be done before or after storage.