3poundsbone-in, skin-on chicken thighs(about 8 to 12 pieces)
Make the marinade: in a container with a lid large enough to hold the chicken thighs, combine the butter, olive oil, vinegar, shallots, garlic, Worcestershire sauce, honey or brown sugar, oregano, salt and pepper. Add the chicken thighs, turning to coat them well with the marinade. Cover and refrigerate for at least 12 hours, up to 36 – the longer the marinating time, the deeper the flavor.
Heat the grill to medium-high, trying to leave some of the grill (gas or charcoal or pellet) a bit cooler. Carefully oil the grates. Place the thighs skin side down one the grill, reserving the marinade. Cook for about 8 minutes (turn them earlier if they start to catch fire or smoke a lot), then baste the chicken and turn the pieces over and cook for another 6 or so minutes, then flip every few minutes, basting once more, until they are cooked through, with an internal temperature of 165° and the juices run clear when pierced with a sharp knife. If there are flareups (which there likely will be), just move the chicken away from the flames to a cooler spot in the grill, and move them back when the flames subside.
Remove the chicken to a cutting board or a serving platter. Let sit for 10 minutes before serving.