Prepare the chicken: Pat chicken thighs dry with paper towel. Brush lightly with olive oil and season generously with salt and pepper.
Preheat the BBQ: Heat your BBQ (or grill pan) with the lid closed until hot — medium-high is ideal.
Sear the skin: Place the chicken skin-side down, lid closed, and cook for 3–4 minutes until the skin is golden with grill marks.
Flip once: Turn the chicken over and cook flesh-side down, lid closed, for another 3–4 minutes.
Finish cooking: Reduce the heat slightly to medium. Keep the lid closed and cook for 12–15 minutes more, or until the chicken reaches an internal temperature of 75 °C (165 °F).
Rest and serve: Remove the chicken, rest for 5 minutes, then spoon the Sauce Vierge over the top and serve immediately.