Gua Bao (Pork Belly Buns)

Steps

1. 1
   Mix the flour, 2 tbsp of the caster sugar, the yeast and baking powder, add the warm water and 1 tbsp of the oil, and knead for 8 minutes to a smooth, soft dough. Cover and leave for 1 hour until doubled.
2. 2
   Meanwhile blanch the pork in boiling water for 3 minutes, drain and rinse. Heat 1 tbsp of the oil in a heavy pan, melt the brown sugar in it until amber, and turn the pork in the caramel.
3. 3
   Add both soy sauces, the Shaoxing wine, star anise, ginger, the spring onions tied in a knot, and the water. Cover and simmer gently for 1 hour 15 minutes until a skewer slides through the pork, then uncover for the last 10 minutes to reduce the liquid to a glaze.
4. 4
   Toss the cucumber with the rice vinegar and salt and leave for 20 minutes.
5. 5
   Mix the peanuts with the remaining caster sugar.
6. 6
   Knock back the dough, divide it into 10 balls and roll each into an oval about 12 × 8 cm. Brush the tops with the last of the oil, fold each in half over a chopstick so it does not seal, pull out the chopstick and rest the buns on squares of baking paper for 20 minutes.
7. 7
   Steam the buns over boiling water for 10 minutes, then leave the lid on for 2 minutes off the heat so they do not wrinkle.
8. 8
   Open each bun and fill it with a slice of glazed pork, a few slices of cucumber, a spoonful of the peanut sugar and coriander leaves.