To marinate the duck, prick the legs all over with a skewer, then put in a large bowl. Add the salt, peppercorns, star anise, cinnamon, ginger and Shaoxing wine. Rub the salt and spices all over the duck legs. Set aside, covered, in the fridge for at least a couple of hours, or overnight.
When ready to cook, drain off any juices and wipe any residue off the duck legs. Place a wok over a medium heat and add 150ml cold water, a cinnamon stick and 40g ginger. Place a bamboo steamer over the pan and line the tray with baking paper.
Place the duck legs on top of the paper and place the lid on top. Steam the legs for 2 hours or until very tender. When done, remove from the steamer and place aside to cool slightly. Reserve the cooking liquor from the pan underneath.
To make the sauce, place all the ingredients in a medium saucepan over a medium heat and cook, reducing until thick and shiny.
Heat some vegetable oil in a deep pan until it reaches 180 C. Place the duck legs in and deep fry until the skin is golden and crispy. Remove from the oil and shred the meat off the bones.
Place the shredded duck on top of the cooked oven chips in a bowl and top with some of the sauce. Finally add some shredded spring onions.