MAKE the Bao Buns. Mix the flour, caster sugar and ½ tsp salt in a large bowl. In another bowl, dissolve yeast and a pinch of sugar in 1 tbsp of warm water. The mixture is ready when it looks frothy. Add the finished yeast mixture to the flour mix along with the milk, avocado oil, rice vinegar and 200ml water. Mix until the dough comes together, adding extra water if needed.
KNEAD the dough on a lightly floured work surface for 10-15 mins, or until smooth. Place the dough in a lightly oiled bowl, cover with a damp cloth and leave to rise for 2 hours, or until doubled in size.
RELEASE excess air within the dough by punching lightly with your fist. Remove the dough from the proving bowl and place onto clean work surface. Flatten the dough with your hands, then sprinkle with baking powder and knead for 5 mins.
ROLL out the dough into a cylinder, about 1 inch thick, then cut into roughly 18 even pieces. In the palm of your hand, roll each piece of dough into a ball and leave to rest for 2-3 mins.
MAKE the filling sauce. In a small bowl, whisk together the hoisin sauce, sriracha, ginger, and lime zest.
ROLL each ball into an oval, about 1/4 inch thick. Rub the surface of the dough ovals with oil and brush a little oil over a chopstick. Place the oiled chopstick in the center of each oval. Fold the dough over the chopstick, then slowly pull out the chopstick.
CUT 18 4-inch squares of baking parchment and place a bun on each. Transfer to a baking tray, cover with a clean tea towel and leave to prove in a warm place for 1 hr 30 mins, or until doubled in size.
HEAT a large bamboo steamer over medium-high heat. In batches, steam the buns for 8 mins until puffed up. Open each bun and fill with your black forest ham, avocados, veggies straws and hoisin sauce mixture. Squeeze a little lime over the avocado, cucumber and carrot. Garnish with mint or cilantro and enjoy while they’re still warm!