Achievement unlocked -- Sourdough Hongkong-style charsiu (and other fillings) bao

Classic charsiu bao

As a maker/baker, i will readily admit that frozen bao and dimsum are staples of our family's Asian market grocery cart for easily-prepared, fuss-free eating for all four in our household. 

Recently though, I decided to deep-dive into making our own freezer stash of Hongkong-style steamed bao -- slightly sweet dough, that signature popped-open top, a size that went easily into heavy snack/small meal. I knew the regular yeasted doughs would produce a good siopao with a smooth surface, but i fixated on that flower-like peekaboo, a cushiony, not-too-bready texture, and of course a well-flavored filling of charsiu pork. Using my sourdough starter, of course.

peekaboo filling is peeking a little too much!

The rabbit hole of what makes the ideal bao bun led me to Souped-up Recipe's Mandy Fu. Some of the ingredients she calls for are specialized, and definitely lean toward the alkaline -- lye water and ammonium carbonate, as well as baking powder. Why? Because the acidity of the fermented starter combines with these to produce a light, cottony texture that has no rise time and should be shaped and steamed immediately. I did this, hunting down baker's ammonia, and the yellow-labelled lye water that weren't available at my regular Asian market -- when I asked the owners, they said nobody used it anymore except big bakeries. 

If bao are the only thing you ever make with a pre-ferment, by all means use Ms. Fu's yeast-based 3-day starter -- it is a build that gives you the exact amount you need for a batch. On the other hand, if you have a starter that is alive and well, a few feeds will get it to the point where it is perfect for this use. 

Most steamed bao doughs use cake flour -- it gives a biscuity, less chewy quality to the end result, and is responsible for the steaming opening up the top because the dough is shaped but not too glutenous.  I wanted something that had some chew, as well as enough structure to hold in the saucy filling. 

It's still a work in progress, but this is by far the closest I have gotten to my own personal charsiu bao goal. It makes 24, because this is to stock the freezer!

Chicken meatball bao

Sourdough build: 

200 g mature sourdough starter

60 g all-purpose flour (bleached ok)

40 g fine rice flour

60 g water

Repeat the same 60% feed every 8-12 hours twice more without discarding any, so that you have approximately 680 g. pre-ferment. This will feel in between a stiff starter and a liquid one, because of the extra starch and 60% hydration. Let rise after the last feed until it doubles, about 6 hours to up to overnight.

Have 24 3x3 paper squares or standard cupcake liners ready, and water for steamer baskets heating.

640 g starter

266 g sugar

40 g shortening or lard

16 drops lye water

Mix until smooth, either with the dough hook or by hand.

1 tsp baker's ammonia

300 g all-purpose flour

60 g fine rice flour (360 g cake flour if you prefer, see above)

2 tbsp baking powder

Knead smooth, then divide into 50 g pieces. Keep covered. Dust the surface with rice flour and roll a piece into a circle. Thin out the edges with a rolling pin, so that the circle is about 4 1/2" wide (12 cm).  

Center 30 g filling* and pinch the top closed into quarters. Try to keep the filling centered and the top not too thick. Place on the prepared paper. 

Repeat to fill a steamer (but don't crowd them -- leave room for the buns to fluff), then place above the rolling-boil water.  If your steamer is bamboo, enough water vapor will escape that your buns will have the needed moisture; but if your steamer cover is metal or glass, secure a kitchen towel around it to absorb extra water so it doesn't drip back down onto the buns and cause spots or sogginess. Steam for 16-18 minutes, tightly covered. 

Remove from the water, but allow to cool for 10 minutes before uncovering so the buns don't collapse. Do the same for all the pieces, setting them onto a rack to cool out of the baskets.

Once the buns are all cooked and cooled, place them in a single layer in a gallon freezer bag and freeze flat. When they are frozen solid, you can stack the bao to conserve space and minimize air in the bag. 

*filling possibilities: charsiu pork or chicken in a gingery, oyster/hoisin cornstarch-thickened sauce (pork/chicken asado); ground turkey or chicken or shrimp meatball with Chinese chives, lap cheong or yun chang sausage and hard-boiled eggs, either quartered or quail ("bola bola"); cornstarch-thickened custard.