Using a sharp knife, make 2 – 3 diagonal slashes in the chicken drumsticks and place them in a large non-metallic dish.
Mix all the ingredients for the glaze together in a jug and season to taste with salt and pepper. Pour the glaze over the drumsticks, turning until the drumsticks are well coated. Cover with clingfilm and leave to marinade in a refrigerator for at least 1 hour.
Preheat the barbecue. Drain the chicken drumsticks, reserving the marinade. Cook the chicken over medium hot coals, turning frequently and brushing with the reserved marinade, for 25 – 30 mins, or until thoroughly cooked.
Transfer to serving plates and serve immediately.