# Preheat the oven to 160°C/Gas Mark 3.
# Peel and trim the sprouts and cut into quarters lengthways.
# Toss in an ovenproof dish with 1 tablespoon of the duck fat and the sugar and season well.
# Bake in the oven for about 15 minutes, until just tender.
# While the sprouts are cooking, brown the bacon in a frying pan in the remaining duck fat, then add the garlic, sage and thyme.
# Cook for 1 more minute, remove from the heat and stir through the breadcrumbs, orange zest and parsley.
# Stir the chestnuts into the sprouts. Pour over the chicken stock. Top with the stuffing mixture and return to the oven for 10 minutes, or until golden.