Clean the duck thoroughly, making sure to remove all residual feathers and any remaining fat, especially around the tail area, which can carry a strong, gamey flavor. Pat the duck completely dry using paper towels.

Season the duck generously inside and out with salt and Chinese five-spice powder, ensuring the cavity is well-coated. For optimal flavor infusion, let the duck marinate for at least 1 hour, or preferably overnight in the refrigerator.

Using a mortar and pestle or food processor, blend the galangal (or ginger), shallots, garlic, white peppercorns, and cilantro roots (if using) into a smooth, fragrant paste. This will serve as the flavor backbone of the braising liquid.

In a heavy-bottomed pot or Dutch oven, heat a small amount of oil over medium-high heat. Place the duck breast-side down and sear until lightly golden. Rotate carefully to brown all sides. As the fat renders, spoon off and reserve the excess duck fat for future cooking—this adds rich flavor to other dishes. Once seared, remove the duck and set it aside.

Lower the heat and add palm sugar to the same pot. Stir continuously until the sugar melts and turns a deep amber color. Immediately add the prepared spice paste along with star anise and cinnamon sticks. Stir-fry briefly, around 30 seconds to a minute, until the mixture becomes aromatic.

Return the seared duck to the pot, turning it gently to coat it in the caramelized spice mixture. Pour in enough water to submerge at least half, or ideally two-thirds, of the duck. Add both soy sauces and fish sauce, stirring well to combine with the other ingredients.

Bring the mixture to a boil, then lower the heat to maintain a gentle simmer. Cover the pot with a tight-fitting lid and allow the duck to braise for 1½ to 2 hours, flipping the bird every 30 minutes to ensure even cooking and a deep, even color throughout.

In the final 30 minutes of cooking, gently nestle in tofu puffs and hard-boiled eggs if using, allowing them to absorb the savory richness of the braising liquid.

Once the duck is tender and the meat nearly falls off the bone, carefully remove it from the pot and let it rest for 10–15 minutes. If the braising liquid is too thin, increase the heat and reduce it uncovered to thicken slightly. Skim off any surface oil for a cleaner finish.

Carve the duck into serving portions and place them on a platter. Spoon the braising sauce generously over the top. Garnish with sprigs of fresh cilantro and sliced spring onions for a bright, herbaceous finish.

Serve hot alongside steamed jasmine rice and, if desired, a tangy dipping sauce made from simmered garlic, sugar, and white vinegar.