Steep 8 chillies in 150 g vinegar in a bowl for at least 2 hours.
Joint 1 duck to separate the breasts and legs. Chop the neck, carcass, and trimmings into chunks and arrange them in a roasting tin with 50 g onion and 50 g carrots.
Warm a dry frying pan over low heat and toast the toasting spices for 2 to 3 minutes until fragrant, then remove from the heat. Transfer the toasted spices to a blender along with the soaked chillies and vinegar, 12 g ginger, 50 g tamarind, and 2 tsp sugar; blitz into a completely smooth paste without adding any water.
Smear the spice paste all over the duck portions, season with salt to taste, cover, and leave to marinate in the fridge for 1 hour.
Preheat the oven to 200°C (400°F). Set the marinated duck pieces on top of the carcass bones and vegetables in the tin and roast, basting occasionally, until the skin begins to brown.
Turn the heat down to 180°C (350°F) and roast further, basting now and then, until the duck is tender and cooked through.
Lift the duck from the roasting tin with a slotted spoon onto a serving dish. Strain the roasting juices into a saucepan, skim off excess fat, and simmer until lightly reduced, then spoon the sauce over the duck.
Use the same weight, skinless and boneless or bone-in as you prefer. Cooks much faster, so add later and simmer 20–30 minutes less; add a little extra oil for richness.
Use 80% of the weight, finely shredded and browned slowly with a pinch of asafoetida. Replicates the bulk and natural sweetness in gravies without allium.
Use the same weight; peel and cut as for carrot. It is less sweet and slightly peppery, so add a pinch of sugar and expect a softer, more earthy result.
Use about a third of the weight (0.5 g ground for a 2.5 cm piece), stirred in with the ground spices rather than fried whole, since the powder burns quickly.
Use 1 g ground for 4 g whole (or 1 small pinch per 2 to 3 whole cloves). Add with spice powders; disperses intense warmth quickly, so use with restraint.
Allspice berries
Use 100% of the weight whole in tempering. Imparts a warm, clove-like aromatic profile combined with hints of nutmeg and cinnamon.