Shanghai's famous steamed buns, commonly called soup dumplings, burst with a liquid centre when eaten. The trotter, which is high in gelatine, is important here, helping to set the stock into a jelly, which means it can be folded into the wrapper. Steam the xiao long bao, and it'll liquify once more. The stock makes more than you need, but freezes well.
- 200 gm picked crabmeat
- Soy sauce, to serve
- Chinkiang vinegar combined with shredded ginger, to serve
- 1.5 kg pork bones
- 1 kg chicken wings
- 1 pig's trotter (see note)
- 120 ml soy sauce
- 80 ml Shaoxing wine
- 4 thick slices of ginger
- 1 head of garlic, halved
- 2 star anise
- 1 piece cassia bark
- 200 gm high-gluten wheat flour (see note)
- 2 tsp lard (See note), plus extra for greasing
- 1For jellied stock, combine ingredients and 2 tsp salt in a large stockpot, cover with water and bring to the boil. Skim scum from surface, then reduce heat to medium and simmer until stock is very well flavoured (3½-4 hours). Strain stock into a shallow, wide container, season to taste with salt, cool, then refrigerate until set (overnight).
- 2For bun dough, combine ingredients in a bowl. Add 120ml boiling water and stir with a fork until dough comes together. Leave until cool enough to handle, then turn out onto a work surface and knead to a smooth dough (2 minutes). Cover with plastic wrap.
- 3Measure out 300gm jellied stock and cut into 2cm cubes.
- 4Lightly grease a worksurface with lard. Dividedough into 20gm (small-walnut size) portions and roll out to transparent 12cm rounds. Working with a round at a time, hold wrapper in the palm of one hand, place 1 tsp crabmeat in centre and top with a cube of jelly. Fold and pleat edges upwards in a circular pattern to form a teardrop shape, then pinch together to seal, trimming excess pastry. Place on a tray lined with baking paper, cover with a tea towel, and repeat to make 16-18 buns
- 5Place buns on squares of baking paper in a steamer and steam in batches over a saucepan of boiling water until cooked through and stock has melted (4 minutes). Serve immediately with soy and vinegar mixed with ginger.
Pig's trotters are available from butchers – you may need to order them in advance. High-gluten wheat flour is available from Asian grocers. Lard is available from select butchers and delicatessens.