Prepare the duck the day before you want to eat it. Slide your fingers underneath the skin and wiggle to loosen it away from the breast meat, working your way down the bird. Put the duck on top of a wire rack in the sink, and pour over a kettleful of boiling water. This will tighten the skin, so it gets extra crispy. Leave the duck to sit for a moment, until most of the water has dripped off, then transfer to a roasting tray, patting the bird all over with kitchen paper to remove the excess moisture.
Combine the soy sauce, honey, salt and five-spice powder in a small bowl, then rub this mixture all over the duck, inside and out. Put the duck, uncovered, in the fridge overnight.
The next day, preheat the oven to 180°C. Put a roasting tray half filled with water at the bottom of the oven (this will catch the fat from the duck as it drips), then place the duck straight onto a wire rack above. Roast for about two hours, until golden and crispy. If you’re worried the duck is burning, you can cover it with foil, but you want it to be really crispy.
Once cooked, let the duck stand, covered, for at least ten minutes. Shred it into small pieces, and serve with the pancakes, hoisin sauce and sliced vegetables, so everyone can assemble their own.