Liu Sa Bao
流沙包·(liú shā bāo)
Chapter 2: The Steamed
To pull off a proper dim sum service at home, you need a closer. That closer is the Liu Sa Bao. Tearing into this impossibly soft, snowy-white bun to reveal a flowing river of savory, golden duck-egg custard is the ultimate flex. It is a precise, unapologetic weekend project requiring exact temperatures, a short proof, and a clever teahouse trick involving vinegar and steam. You don't whip this up on a Tuesday. You build it deliberately on a Saturday to rule Sunday morning.
Before you start
Bloom the gelatin.
Mix the gelatin powder with the cold water in a small ramekin and let sit for 5 minutes. Microwave for 5 to 10 seconds just until melted before adding to the filling.
Ingredients
- cooked salted duck egg yolks60 g
- Shaoxing wine1 tsp
- unflavored gelatin powder1/2 tsp
- cold water1 tbsp
- unsalted butter60 g
- icing sugar45 g
- full-fat milk powder25 g
- custard powder15 g
- evaporated milk20 g
- bleached cake flour250 g
- all-purpose flour50 g
- instant dry yeast3 g
- double-acting baking powder5 g
- caster sugar30 g
- whole milk150 g
- neutral oil10 g
- distilled white vinegar1 tbsp
Method
- 01
Cook and mash the salted yolks.
Spritz the cooked duck egg yolks with the Shaoxing wine to mellow their gaminess, steam for 8 to 10 minutes until completely opaque, then mash them into an exceptionally fine, gritty paste.
- 02
Whip the molten matrix.
In a medium bowl, vigorously beat the softened butter and icing sugar until pale, then mix in the milk powder, custard powder, and evaporated milk until a thick paste forms.
- 03
Fold and chill the filling.
Fold the mashed yolks and melted gelatin into the butter mixture until completely homogenous, then refrigerate for 30 minutes to firm up.
- 04
Portion and freeze the core.
Roll the chilled filling into twelve equal spheres. Place them on a parchment-lined plate and freeze overnight until rock hard.
- 05
Mix the snowy-white dough.
In a stand mixer, combine the lukewarm milk, yeast, and sugar. Let sit for 5 minutes, then add the cake flour, all-purpose flour, baking powder, and neutral oil.
- 06
Knead to a glass-smooth finish.
Knead on medium speed for 8 to 10 minutes until the dough is incredibly smooth and elastic, pressing out all interior air bubbles.
- 07
Rest the dough briefly.
Cover the dough with a damp towel and let it rest for exactly 15 minutes to relax the gluten without starting a massive, flavor-altering fermentation.
- 08
Divide and roll the wrappers.
Punch down the dough, roll it into a log, and cut into twelve pieces. Roll each into a 3.5-inch disc with thinner edges and a thicker center to support the heavy filling.
- 09
Encase the frozen core.
Place a frozen filling sphere in the center of each wrapper, pleat the edges up, and pinch firmly to seal. Place the bun seam-side down on a square of parchment paper.
- 10
Proof the buns.
Arrange the assembled buns in bamboo steamer baskets with 2 inches of space between them, and proof in a warm place for 30 to 40 minutes until visibly puffy.
- 11
Execute the Hong Kong teahouse steaming trick.
Bring a wok of water to a vigorous boil and pour in the white vinegar. The vaporized acetic acid will neutralize the dough's alkalinity, preserving a pristine white exterior.
- 12
Steam with absolute precision.
Place the covered bamboo steamers over the boiling water and steam on medium-high for exactly 8 minutes.
- 13
Rest before revealing.
Turn off the heat and wait exactly 3 minutes before carefully lifting the lid. This critical pause prevents the dreaded thermal shock that causes delicate buns to collapse and wrinkle.
Notes
Sourcing the right ingredients is non-negotiable.
Look for Bird’s Custard Powder or Lion brand at an Asian grocer. It is vital for that signature teahouse vanilla aroma and brilliant golden hue.
The short proof is the secret to success.
Because the filling is frozen, a long secondary proofing time will cause the center to melt and bleed through the raw dough before it ever hits the steamer. Keep the proof brief.
From Cook Dim Sum at Home.