1. Toss the olive oil, red onion, chicken, garlic, cumin and chipotle powder together in a bowl until completely coated. Place a large griddle pan over a high heat until hot, then add the chicken and red onion and allow to char on all sides until the chicken is cooked through and the red onion wedges are tender. Keep warm in a low oven while you prepare the toppings.
2. Toss the shredded red cabbage with the lime juice, a good pinch of sugar and some seasoning. Add a drizzle of extra virgin olive oil and set aside to pickle.
3. Spoon the chicken and onion wedges onto warmed tortillas and top with pickled cabbage, sliced red onion, avocado slices, dollops of guacamole and a scattering of coriander. Squeeze over lime wedges, roll up and devour.