Rub chicken inside and out with combined seasoning (A). Hang the bird in an airy place to dry.
Parboil potatoes and chestnuts until tender. Simmer carrots in boiling water until soft. Drain.
Saute garlic and onions in melted butter and oil till fragrant. Add button mushrooms, cooked chestnuts, potatoes and carrots. Mix in seasoning and stir-fry well. Dish out to cool slightly.
Add breadcrumbs and beaten egg. Mix well.
Stuff filling into cavity of chicken. (Do not pack too much filling or the skin may burst during cooking.) Secure the opening with two or three cocktail sticks or sew up with thick thread.
Bring the combined glaze ingredients to a low boil for five to l0 minutes. Leave aside to cool completely. Brush chicken evenly with cooled glaze mixture.
Place chicken on a roasting tray, breast side down, brush lightly with melted butter and roast in a preheated oven at 190ºC for 30 to 35 minutes.
Remove tray from oven and turn the bird breast side up. Brush with glaze and roast for 10 minutes. Remove tray from oven and brush bird with melted butter and glaze then continue to roast for a further 50 to 60 minutes or until cooked through.