Combine the soy sauce, sesame oil, olive oil, honey and crushed dried chillies in a shallow dish. Add the whole chicken breasts, cover and leave to marinate for 3–4 hours in the refrigerator.
Preheat a griddle pan over a high heat until hot, then add the chicken, reduce the heat to medium, and cook for 8 minutes on each side, until char-grilled and cooked through. Wrap in foil and leave to rest for 5 minutes.
Meanwhile, mix all the salsa ingredients together and season with salt and pepper. Set aside to infuse.
Strain the marinade juices into a small saucepan and bring to the boil, then remove from the heat.
Serve the chicken with the couscous tossed with diced tomato and top with the salsa and the warm marinade.