The night before whisk well all the marinade ingredients in a walled flat dish and toss in the chicken fillets to get well coated. Place in the refrigerator covered with plastic wrap.
An hour before cooking take the chicken out of the refrigerator.
In the meantime, turn on the oven to 100°C max temperature with the air circulation and elements (not broiler) on, and set the rack to the middle position.
Take an oven-proof dish and place the chicken pieces in it. Brush some of the remaining marinade on them and place in the oven and grill for 25’ turning 15’ later and basting with the remaining marinade, aiming for a bit of charred colour to be achieved.