Three hours ahead—or the night before—make the marinade. Mix together the balsamic vinegar, soy sauce, dark brown sugar, honey, grated garlic and all the seasonings.
Set aside a small cup of the marinade.
Add the drumsticks in the remaining marinade and cover the dish with cling film.
Light a charcoal grill; a ridged grill-pan will also work if you have no barbecue.
When the coals are glowing and the temperature is right (no open flames), lay the drumsticks on the grate and cook about 15-20 minutes per side. The exterior will darken from the sugar and honey – that’s normal.
A few minutes before the drumsticks come off the grill, baste them with the reserved marinade.
Transfer to a platter and sprinkle with sesame seeds and chopped spring onion.
