Pare the zest from the orange in thick strips then mix with the soy sauce, sherry and fivespice powder in a large food bag. Bash the garlic cloves and ginger with the back of a knife to bruise them, then add to the bag and give everything a good mix.
Put the chicken in the bag, rub the marinade all over the flesh then leave to marinate in the fridge for at least 3 hrs, overnight ideally.
Heat oven to 190C/fan 170C/gas
Remove the chicken from the marinade (keep it for later). Halve the orange and put both halves inside the cavity along with the bashed ginger and garlic from the marinade. With the chicken sitting on a rack in the sink, pour a kettleful of boiling water over it. Pat completely dry with kitchen paper. Set the chicken on its wire rack over a roasting tray and roast for 50 mins per kg or until the juices run clear when the thigh is pierced with a skewer.
Strain the marinade into a pan along with the honey. Bring up to the boil then simmer for a couple of mins. Just before serving, turn the oven up as high as it will go.
Brush some of the marinade all over the chicken. Return to the oven and cook until the chicken is crisp and browned. This will only take a couple of mins. Leave to rest, uncovered, for 5 mins.
Serve with the remaining warmed marinade, some plain rice and bok choi or spinach stirfried with a little garlic and oyster sauce.
