In a saucepan or the microwave oven, bring the milk and half of the water up to room temperature. The liquid needs to be tepid, not hot. Sprinkle with the dried yeast, and set aside while the yeast rehydrates.
In a mixing bowl, mix the plain flour with the caster sugar. Form a well in the centre of the dry ingredients, pour the milk mix and the oil. Mix together until you obtain a soft and sticky dough: if the dough is too stiff, add the remaining water by the spoonful, until the dough becomes soft and manageable.
Tip out the dough onto a lightly floured surface, and knead for about 10 minutes, or until it feels less sticky.
Return the dough to the bowl, cover with a damp cloth or cling film, and leave to prove in a warm place until nearly doubled in size.
While the dough is proving, cut out 5*5cm squares of baking parchment, and prepare the filling.
When the dough has risen, knock it back and divide into equal parts, and form into balls. Full sized buns are normally weighted at 100g, while smaller buns should be about 50-75g.
Roll out each ball into a disk about 5mm thick. Lightly oil the dough's surface, and fold over. To ensure that the two halves do not stick, you can sandwich a piece of baking paper.
Place each folded bun on a square of baking paper, and onto a tray. Loosely cover with cling film, and prove until nearly doubled in size. While the proving period can be shortened by placing the dough in a very warm place (22-24'C), the dough keeps its shape better when proved slowly in cooler conditions (18'C).
When ready, place the buns on a steamer rack, and leave to steam for 20 minutes.
Peel and finely chop the ginger and garlic.
Wash and dry the bok choi, and shred.
Remove the stalks from the shiitake mushrooms, and slice the caps.
Finely chop the spring onions, and set aside.
Mix the mayonnaise and hoisin sauce together, and set aside.
Heat the oil in a wok. Stir fry the shiitake mushrooms.
When the mushrooms begin to brown, stir in the garlic, ginger, bok choi and five spice.
Split open the steamed buns, and fill with the stir-fried vegetables.
Dollop with the hoisin mayonnaise and sprinkle with the sliced spring onions.
«You can fill the buns with anything you like, including left-overs from roast dinner, or even sweet ingredients, such as chocolate or custard. If you are cooking several types of filling at the same time, fold the buns in different manners to distinguish the fillings. You can also mark the buns with a spice mix to reflect the filling inside.»
Asian steamed buns are all the rage at the moment: these tasty morsels are not only exotic and familiar at the same time, they are incredibly portable. Impress friends and family by making your own.