No Sweet Sour: Yunnan Posubao (破酥包)

Published Jul 13, 2021, Updated Feb 16, 2024

Yunnan’s Flaky Baozi

Iconic 破酥包 (pòsūbāo), literally translated as “crumbly bun,” is a unique steamed 包子 (bāozi) from Yunnan province. Its flaky layered skin is stuffed with either sweet or savory fillings. The origin tale dates back to 1903, when the pastry chef 赖八 (Lai Ba) of Yuxi invented posubao by adding lard to his baozi dough. The addition of lard made the wrapper cloud-like, with a loose and mouth-melting texture.

Unlike neatly folded 小笼包 (xiǎolóngbāo), or soup dumplings, posubao has almost no folds. Instead, it has a fragile appearance, as if if you touch it, it will fall into pieces. These characters inspired the name 破酥, “broken” and “crumbly.”

a closeup of a meat filling posu bao that shows all the layers in the dough — Posubao are the croissants of baozi

a stacked bamboo steamer with four steamed posu bao — Posubao are the croissants of baozi

Clarissa Wei compares posubao to croissants in this episode of Eat China for Goldthread.

There are numerous places in Kunming that are famous for making posubao, including 翠满珑 (Cui Man Long) located on 人民东路 (Renmin Donglu). All of their buns are freshly made right before selling. Every time I passed by, I would buy a few to go. When I received them in my hands, they would still be warm. The moment I’d unwrap the bag, I’d sense a tempting scent of lard float right into my nose, making it impossible to resist taking a big bite.

The bite would further release all of the flavors wrapped inside. If it was a sweet posubao, a sugary filling with small bites of ham would flow out. If it was savory, my mouth would instantly be filled with aromatic shiitake mushroom flavor. In less than five minutes, I would finish two to three buns, the perfect amount for a quick lunch.

a bamboo steamer stacked with six posu buns in a flower arrangement — Posubao can be steamed in advance, then frozen for later

a bamboo steamer with four steamed buns including one split open to show the flaky inside and jujube filling — Posubao can be steamed in advance, then frozen for later

Another famous and currently best-selling pastry place for posubao is 福祥聚 (Fu Xiang Ju) on 桃源街 (Tao Yuan Jie). My mom has experienced waiting for almost four hours in the long queue to buy the buns that many others sought. Many people buy 50-100 buns of different flavors at a time to share with family and friends or freeze for later. The pastry shop now only takes pre-orders, meaning customers must visit at least one day ahead to place their order, then pick up the buns on the following day according to the agreed time. The buns are packed in portions of five, sorted according to the flavors. They put a green dot on the savory buns and a red dot on the sweet buns to distinguish between them.

The most classic fillings are savory shiitake pork and sweet ham and sugar. Other fillers such as fermented mustard green and pork, bamboo and pork, red bean paste and black sesame are some of the most popular ones.

showing the step by step process of making posu bao dough and wrapping — Follow this step-by-step guide to making your own posubao at home

Making Posubao at Home

A big challenge for creating a posubao recipe is understanding how the dough is prepared. From my research, I noticed many mentioned making posubao dough using 低筋面粉 (dījīn miànfěn), a low-gluten cake flour. In a professional pastry setting, they would use 老面 (lǎo miàn), like sourdough, to proof the dough. Sometimes a small amount of baking soda is also added to boost the flaky layer effect.

For home cooking, I would recommend using fresh or active dry yeast.
If you are unable to source cake flour (generally between 6.5-9% gluten by weight), replace the 230 grams low-gluten flour called for with 200 grams of all-purpose flour and 30 grams of cornstarch.
Lard is key to both the flavor and flakiness, so be sure to use a high-quality pork lard that you make yourself or purchase from a butcher.
Another important thing to note while preparing the dough is that when you roll out the dough, the thinner the sheet gets, the more layers the buns will have in the end. However, if you roll the sheet too thin, the layers may get laminated back together. So aim for a long and even rectangle-shaped sheet that is 2-3 millimeters thick.
Divide the dough by hand instead of using a dough cutter. This helps support the structural integrity of the layers. Using a knife or dough cutter leaves a slightly different texture on the side where the dough is cut. It’s like the difference between hand-shredding chicken breast and cutting it with a knife.
When wrapping the buns, keep the folds as simple as possible. Layers of folds will result in reducing the layers of buns after they are steamed.

The recipe for the dough here makes about 8-10 buns. If you wish to double the recipe, you can freeze the buns after steaming, for up to one month. Reheat directly without unfreezing the buns.

If you loved this recipe, check out Michelle’s guide to hand-wrapping Three Umami Dumplings in Emerald Jade Wrappers (San Xian Jiaozi, 三鲜饺子)!

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No Sweet Sour: Yunnan Posubao (破酥包)

By: Michelle Zhao @nosweetsour | The Mala Market

Equipment

Steamer

Ingredients

Jujube Filling (fills 8)

100 grams dried jujube, pits cored
1 tablespoon peanut oil or other neutral oil
50 grams walnut, toasted and crushed
2 teaspoons toasted white sesame seeds

Shiitake Pork Filling (fills 8)

8 large dried shiitake mushrooms
2 tablespoons Chinese rapeseed oil (caiziyou)
1 teaspoon minced fresh ginger
100 grams minced pork (at least 20% fat) approx. 3.5 ounces, see note
1 tablespoon Shaoxing wine
1 tablespoon Chinese dark soy sauce (laochou)
1 tablespoon Chinese sweet soy sauce
1 teaspoon ground white pepper
1 teaspoon salt
½ tablespoon cornstarch

Posubao Dough (makes 8)

230 grams low-gluten wheat flour such as cake flour
⅛ teaspoon baking soda
130 grams lukewarm water
2 teaspoons sugar
2 teaspoons active-dry yeast
25 grams unbleached all-purpose flour more for dusting
25 grams freshly made lard

Instructions

Jujube Filling

In a small pot, cook the jujube in about 1½ cups (350 mL) water over medium heat. Cover the pot with a lid; this will take about 20 minutes. They are sufficiently rehydrated when the jujubes become plump and soft and the water is almost reduced.
Transfer the jujube to a blender. Pulse and blend into a fine, runny paste. Using a strainer, pour the paste through the sieve onto a non-stick pan.
Add the peanut oil. Fry the paste over medium-low heat to draw out the moisture. Stir every 1-2 minutes to avoid it sticking to the bottom of the pan.
Gradually, you will notice the runny paste becoming thicker and the color getting darker. Once the paste reaches a dense, dry consistency (like cream cheese), add the crushed walnuts and sesame seeds to combine well. Transfer to a bowl to cool down.
The filling can be prepared several days ahead, stored in the freezer using a freezer-safe bag/container.

Shiitake Pork Filling

Soak shiitake mushrooms for at least 2 hours and up to overnight in cold water. Cut the mushrooms into strips, then mince roughly using a knife or food processor. Reserve about 1 cup + 2¾ teaspoons (250mL) of the shiitake mushroom soaking water.
Heat oil over medium heat. Add the minced ginger and fry until it smells good. Add the pork and fry until the fat starts to release. Season with Shaoxing wine, dark soy sauce, sweet soy sauce, white pepper powder and salt. Add minced shiitake mushroom, ½ tablespoon cornstarch and the reserved shiitake mushroom soaking water. Simmer for 5 minutes until water is reduced and the filling thickens.
Transfer into a covered bowl and let the filling chill in the fridge until you are ready to begin wrapping. The filling can be prepared one or two days ahead.

Posubao Dough (makes 8)

Whisk together the low-gluten flour, baking soda, sugar and yeast for the dough. Add the lukewarm water and combine well. Like all baozi dough, the dough will be pretty soft at this point. Knead into a soft and smooth dough—but do not over-knead, as that may activate the gluten and result in less-fluffy baozi. Cover with a damp towel and let the dough proof to twice its size.
If you are making this in the winter, or keep the house below 68°F (20°C), the dough will take longer to proof. To mitigate this problem, you can use your oven as a proofing box or even a microwave.
While the posubao dough is proofing, combine the lard and AP flour into a lard dough (see note). Set aside.
Dust flour on a flat, clean surface. Press on the posubao dough to let the air out. Then roll the dough out into a thin, rectangle shape. Using a scraper, apply a thin layer of the lard dough across the top and dust with a thin layer of AP flour. Then, starting from one edge, roll the dough into a long, thin roll. Divide into 2 long sections.
Gently roll one of the logs to adjust the shape. Then, divide the log into 4-5 equal sections by hand. Repeat with the second log. Let the pieces rest for 10 minutes or so before starting to wrap, giving the wrapper time to relax so it will be easier to wrap the baozi.
Take one piece of the divided dough and fold the corners towards the middle to form a round ball shape. Then, press it with your palm to flatten the dough into an approximately 4-inch (10-cm) wide wrapper. Repeat with the rest.
Place 1/8th of the filling in the middle of a wrapper. Fold into a simple bun shape, with as few folds as possible. Be sure to make a tight closure on the top.
Transfer the buns to a steamer with a small piece of baking paper or cheesecloth on the bottom. Let the buns proof in a warm place for 15 minutes.
In a wok or other steamer-compatible wide pot, bring a couple inches of water to a boil on full heat. Once boiling, place the steaming racks on top. Set a timer for 10 minutes before turning off the heat.

Notes

For meat filling: Alternatively, you can select pork belly instead of minced pork. Dice the pork belly into about 0.2 inch (0.5 cm) cubes.

For lard dough: I add AP flour to keep a firm consistency to the lard so it doesn’t become too runny. I once tried to apply lard directly on the dough, it was too runny and became impossible to work with.

To make your own lard:

Rinse about 14 ounces (400 grams) pork fat under cold water, tap dry with kitchen paper. Using a sharp knife, cut the fat into 2cm wide pieces.
Add about ⅓ cup (80mL) water and pork fat in a wok. Bring water to boil. Continue to cook until the water is completely reduced.
Turn the heat down to medium heat once the water is reduced. You will notice the fat beginning to release. Stir once every two minutes.
Once there is more liquid coming out into the wok pan, the pork fat turns into a golden brown color. You can turn off the heat. Pour the liquid lard into a sealable jar through a strainer.
Reserve the strained pork pieces if you wish. They make a crunchy noodle topping.
Store the sealed jar in the fridge for up to 2 months. Use a clean spoon to scoop lard every time you use it.

Tried this recipe?