1.Trim the excess fat from the chicken thighs and discard. Combine the dark brown sugar, salt, five spice powder, white pepper, hoisin sauce, rice wine, soy sauce, sesame oil, and garlic in a bowl to make the marinade. Rub the chicken with the marinade in a large bowl. Cover and refrigerate overnight, or at least 8 hours.
2.About 2½ hours before you’d like to eat, take the chicken out of the refrigerator to come up to room temperature. Preheat your oven to 375°F and set the rack in the center of the oven.
3.Line a sheet pan with a sheet of parchment paper. Evenly space the marinated chicken thighs on the sheet – they should not be touching each other. Reserve any remaining marinade.
4.Transfer the chicken to your preheated oven, and roast for 30 minutes. Check on it every 15 minutes. If the chicken is starting to scorch or burn, tent it with foil and/or lower the oven temperature.
5.Meanwhile, pour the excess marinade into a small saucepan with the water. Heat the mixture to a simmer. Add the honey and mix until combined into the marinade and turn off the heat.
6.After 30 minutes, use a brush to baste the chicken with the cooked marinade. Continue roasting for another 5-10 minutes, and check the internal temperature of the chicken using an instant read thermometer. It’s done when it reaches 165°F and/or when the juices run clear when the meat is pierced to the bone.
7.Give the chicken one last basting and another minute in the oven for that extra char siu crust before serving.