Prepare the bird: pat the Duck dry inside and out, remove any excess fat from the cavity, and season the inside lightly with Salt.
Tighten the skin: bring a pot of Water to a rolling boil and carefully pour it over the duck’s skin (or use a ladle) to shrink and tighten the skin; then dry thoroughly with paper towels and let cool on a rack.
Make the lacquer glaze: in a small saucepan combine Maltose, Chinese Rice Vinegar and a splash of Water with a pinch of Salt; warm gently, stirring, until the maltose dissolves to a syrupy glaze.
Glaze and dry: brush the syrup all over the duck skin, then place the duck on a rack (or hang it) in a cool, well-ventilated spot or uncovered in the fridge for several hours or overnight to dry—this helps achieve that signature crispiness.
Roast the duck: preheat the oven to high (about 220°C/425°F). Roast the duck on a rack for 20–25 minutes to start the crisping, then lower the heat to 180°C/350°F and continue roasting another 30–40 minutes until the skin is deep golden and crisp and the juices run clear. Baste once or twice with any remaining glaze during roasting.
While the duck rests, make quick pancakes: mix All-Purpose Flour with warm Water, a pinch of Salt and a little Sesame Oil to form a soft dough. Rest 20–30 minutes, divide into small balls, roll very thin, and cook briefly in a dry skillet until set and lightly spotted. Brush finished pancakes with a touch more Sesame Oil.
Prepare condiments and veg: spread Sweet Bean Paste on the pancakes (or mix it with a little Sugar and Sesame Oil to taste for a smoother sauce). Cut the Spring Onions into long thin matchsticks and slice the Cucumber into crisp batons.
Carve and assemble: let the roasted duck rest 10 minutes, then carve into thin slices. Serve by spreading pancakes with the sweet bean paste, topping with duck slices, and adding Spring Onions and Cucumber for crunch—wrap and enjoy.
