Taco spice mix:
Mix all the spices together and store in a spice jar or well sealed bottle.
Place all the dressing ingredients in a small bowl and whisk together. Pour into a squeeze bottle for easy use.
For the chicken tacos:
Drizzle 1 tablespoon olive oil over the chicken fillets and season on both sides with the taco spice mix. Place in a non-metallic dish, cover with cling film and leave to marinade for a few minutes. If you have the time, leave overnight in the refrigerator.
Heat the remaining tablespoon of olive oil in a pan and add the chicken fillets once the oil is really hot. Brown on one side, season with a little more salt and turn over. Turn the heat down to a medium high and continue to cook until it is dark and caramelised on all sides. Spritz over the juice of half a lemon. Deglaze the pan with a splash of water and turn the chicken over to coat in the sauce. Remove the chicken from the pan and rest, covered, for 2 minutes before carving into slices. Scrape all the lovely pan juices over the chicken.
Heat the tortillas separately in a pan or for a few seconds in the microwave. If you’re heating the tortillas in the oven, remember to cover them tightly in foil to prevent drying out. To assemble, lay the tortillas out on a large board and start with a handful of purple and green cabbage. Followed with the chicken slices, red peppers, scallions, coriander or parsley and extra chilli, if you like. Drizzle over a generous amount of the buttermilk dressing, hit it with an extra squeeze of lemon, fold up and tuck in!