Prepare the chicken and marinade: Cut the chicken fillets into strips. Finely chop the jalapeño (removing seeds for less heat), grate the garlic, and finely chop the coriander. Mix with sunflower oil, soy sauce, Worcestershire sauce, lime juice, and orange juice. Toss the chicken in the marinade and refrigerate in a sealed bag for at least 2 hours, ideally longer.
Make the guacamole: Halve the avocados and remove the pits. Mash with a fork and stir in lime juice, finely chopped garlic, and coriander. Season with salt and pepper as desired.
Prepare the vegetables: Clean the peppers and slice into strips. Cut the red onion into wedges.
Cook the chicken: Heat a large frying pan with a little oil over high heat. Fry the chicken strips in batches until golden on all sides. Remove and set aside.
Cook the vegetables: In the same pan, quickly fry the peppers and onions until just tender but still vibrant.
Combine chicken and vegetables: Return the chicken to the pan with the vegetables and let everything simmer together for 2–3 minutes until heated through.
Warm the tortillas: Heat wheat tortillas according to package instructions.
Assemble the fajitas: Fill each warm tortilla with guacamole, sizzling chicken strips, and vegetables. Garnish with pomegranate seeds, fresh jalapeño slices, and chopped coriander if desired. Serve with lime wedges for squeezing!