1. Place duck on a rack over a deep roasting tin. Pour over the hot water and leave on one side until the water has drained away from the bird.
2. Discard water and leave duck exposed to air until it's dry to the touch.
3. Mix the honey, soy sauce, five spice powder and brown sugar together. Using a pastry brush, brush this over the duck, inside and out.
4. Leave the bird to dry once more. There should now be a thin glaze all over the bird. Give the duck another coat of sauce and leave to dry once more. Keep repeating the process until all sauce has been used up.
5. Preheat the oven to 200C/gas 6. Roast the duck for 30 minutes before turning it over and cooking for another half hour, until the skin has crisped. Remove from the oven and leave to cool for about 15 minutes. Joint the duck and slice its meat off the bone.
6. While duck's roasting, make the sauce. Warm a wok over a moderate heat, add the sesame oil, hoi sin sauce, caster sugar, water, soy sauce, and the cornflour and water mixture. Bring to a simmer, stirring, and cook down until the sauce has thickened. Leave to cool.
7. Warm the pancakes in a bamboo steamer for 4 minutes. Spread a teaspoon or so of sauce over each pancake and scatter a little of the spring onions and shredded cucumber. Top with a generous helping of sliced duck meat. Roll up the pancakes into a cigar shape and serve.