Xiaolongbao (小籠包, literally "small basket bun") are one of the most technically demanding dumplings in Chinese cuisine — not because the flavors are complex, but because every element must be precisely executed to produce the defining experience: biting through thin translucent skin to receive a mouthful of hot soup alongside tender pork filling.
The dumplings come from Nanxiang, a town near Shanghai, in the 19th century, and have been associated with Shanghai cuisine ever since. Din Tai Fung, the Taiwanese restaurant chain (founded in Taipei in 1972, originally a cooking oil business), codified the modern XLB standard and made xiaolongbao internationally famous.
The Gelatin Trick: How the Soup Gets Inside
The question every first-time XLB eater asks: how is there liquid inside a raw dumpling that gets sealed before cooking?
The answer is that the soup starts solid.
Pork aspic (the gelatin): A pork stock — made by simmering pork skin, bones, or trotters (collagen-rich parts) for several hours — is chilled overnight until it sets into a solid gel. This is pork aspic or dongpo gelatin in the context of XLB.
Assembly: When the dumpling is filled, a piece of this solid gelatin is placed alongside the raw pork filling inside the wrapper. The dumpling is sealed with 16 to 18 pleats.
Steaming: During the 8 minutes of steaming, two things happen simultaneously. The filling cooks. The solid gelatin, exposed to steam at 100°C, melts back into liquid soup — which is now trapped inside the sealed dumpling.
When you bite in: The soup is under slight pressure inside the closed dumpling. The filling is cooked pork in hot soup. The skin is thin enough to be translucent.
This technique — the solid-gelatin trick — means you cannot rush XLB. The gelatin quality determines the soup quality. Weak gelatin produces little or watery soup; properly made aspic produces a full, rich spoonful.
Making the Pork Aspic
- 500g pork skin (or pork trotters, or a combination of pork neck bones with skin)
- 1 tablespoon Shaoxing rice wine
- 2 slices ginger
- 1 green onion stalk
- Salt
Method: Blanch pork skin in boiling water for 2 minutes; discard water. In a fresh pot, cover pork skin with cold water, add rice wine, ginger, and green onion. Bring to a boil, reduce to a simmer, cook 1.5–2 hours until very soft and the liquid is reduced by roughly half.
Strain the liquid; season with salt. Pour into a container. Refrigerate 4+ hours or overnight until completely set.
When set, the aspic should be firm enough to dice with a knife. Cut into 5mm cubes for easy assembly.
The Wrapper
XLB wrappers are thinner than regular dumpling wrappers and made without egg (hot water dough, not egg dough):
- 200g all-purpose flour
- 90ml just-boiled water
- Pinch of salt
Pour boiling water over flour with salt; mix with chopsticks until shaggy, then knead until smooth, 8–10 minutes. Rest 30 minutes covered. Roll as thin as possible — almost translucent, 1–1.5mm. Cut into circles approximately 8cm diameter.
The thinness is structural: too thick and the wrapper overwhelms the soup and filling; too thin and it breaks during assembly or handling.
The Filling
Pork filling:
- 250g ground pork (80/20 lean/fat — the fat carries flavor and keeps the filling from drying)
- 1 tablespoon Shaoxing rice wine
- 1 tablespoon light soy sauce
- 1 teaspoon sesame oil
- 1 teaspoon sugar
- ½ teaspoon salt
- ½ teaspoon white pepper
- 2 teaspoons ginger, grated
- 1 green onion, finely minced
- 2 tablespoons water or cold chicken broth (added gradually while mixing, for juiciness)
- 80–100g diced pork aspic (from above)
Mix pork with all seasonings and aromatics until the mixture has a slightly sticky, cohesive texture. Fold in diced aspic at the end — the aspic should remain as solid pieces in the raw filling; it will melt during steaming.
The 18-Pleat Standard
Din Tai Fung set 18 pleats as the quality standard for XLB, and it became the industry benchmark. The pleats serve a functional purpose: they seal the dumpling completely and create a topknot that can be lifted with chopsticks without breaking the skin.
Pleating technique: Place roughly 1 tablespoon of filling in the center of the wrapper. Using the thumb and index finger of your non-dominant hand to hold the wrapper, use your dominant hand's thumb and index finger to create overlapping folds working around the circumference, pleating each fold over the previous one. Twist and seal the final pleat firmly.
16 pleats is acceptable for home cooking. 18 is the restaurant standard. Fewer than 14 risks sealing failure. More than 18 is impressive but has no functional advantage.
How to Eat Xiaolongbao (Without Burning Yourself)
This is the question: the soup inside is at boiling temperature when the dumpling comes out of the steamer. Biting directly in produces a soup burn to the mouth.
The correct technique:
- Pick up one XLB carefully with chopsticks by the topknot — the twisted pleated top
- Set it on the soup spoon that comes with the dish
- Bite a small hole in the side of the wrapper — just big enough to allow soup to drain
- Drink the soup through the hole — carefully, the soup is very hot; blow on it
- Dip the deflated dumpling in the dipping sauce
- Eat the dumpling whole
The dipping sauce: Black vinegar (Zhejiang black vinegar is the standard) with julienned fresh ginger. The black vinegar's acidity cuts through the pork fat and soup richness; the ginger adds warmth. No soy sauce in the dipping sauce — the filling is already seasoned.
Where to Eat
Din Tai Fung: Taiwanese-origin chain, now international (US, Australia, Japan, Korea, Singapore, Indonesia, multiple other countries). The benchmark for consistent quality at scale. The pork and crab XLB (蟹粉小籠包) with crabmeat in the filling is the premium version.
Jia Jia Tang Bao (Nanxiang Steamed Bun Restaurant) — Shanghai: The Nanxiang flagship, on the City God Temple complex, with permanent queues. Considered by many to serve the most authentic version.
For XLB outside major Chinese cities or Taiwan: The Din Tai Fung chain maintains consistent quality that most independent restaurants do not match at scale. At a newer or untested restaurant, assess by looking at the pleats (more is better), the skin thickness (should be translucent when held to light), and the amount of soup (should be an audible sound of liquid when a dumpling is gently pressed).
Related reading: Dim Sum Guide — Yum Cha and What to Order | Gyoza Guide — Japanese Dumplings | Mandu — Korean Dumplings Guide
The full recipes live in the book.
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