Steamed Bao Buns

Before you start

Steamed bao are a yeasted wheat dough cooked in steam instead of an oven, so they never form a crust. The goal is a smooth, bright white skin and a fine, springy crumb. Low-protein flour, a little sugar and a touch of baking powder alongside the yeast give that soft, fluffy texture; bread flour makes them chewy and gray.

This dough works two ways. Roll it into ovals and fold them over oiled parchment for open gua bao, the kind stuffed with braised pork belly, or wrap and pleat it around a cooked filling for round buns. The common failures happen at the stove: water boiling too hard, condensation dripping onto the buns, or lifting the lid too soon. Steam over a steady medium heat and let the buns rest in the closed steamer for a few minutes before you uncover them.

Ingredients

• 300 g (2½ cups) all-purpose flour — low-protein, about 10%, or Asian bao or Hong Kong flour
• 30 g (2½ tbsp) granulated sugar
• 4 g (1¼ tsp) instant yeast
• ¾ tsp baking powder
• ½ tsp fine salt
• 165 ml (⅔ cup + 1 tsp) warm water or whole milk — about 35°C (95°F); milk gives a whiter, softer bun
• 1 tbsp neutral oil — plus more for brushing

Method

1. Whisk the flour, sugar, yeast, baking powder and salt in a bowl. Add the warm water or milk and oil and stir into a rough dough.
2. Knead by hand for 10 to 12 minutes or in a mixer on low for 7 to 8 minutes. The dough should be firm, completely smooth and not sticky; a smooth dough gives a smooth bun skin.
3. Cover and let rise at warm room temperature for about 1 hour, until roughly 1½ times its original size. Unlike oven bread, bao dough does not need to fully double.
4. Punch the dough down and knead it for 1 minute to press out large bubbles, which would show as blisters. Divide into 12 pieces of about 43 g and roll each into a ball. Keep them covered.
5. Roll each ball into an oval about 12 by 8 cm (4¾ by 3 in). Brush the top lightly with oil, lay a chopstick across the middle, fold the oval over it and slide the chopstick out. Set each bun on a parchment square.
6. Arrange the buns in the steamer, leaving 3 cm between them. Cover and proof for 20 to 30 minutes, until they look slightly puffy and feel light.
7. Bring 5 cm (2 in) of water to a boil in the wok, then lower to a steady medium. Wrap the steamer lid in a towel to catch condensation. Set the basket over the water and steam for 10 to 12 minutes.
8. Turn off the heat and leave the lid on for 5 minutes, so the buns do not deflate from the sudden temperature change. Then lift the lid away from you and steam the second batch.

Tips for success

• If your buns keep wrinkling, set them over cold water instead of boiling water; they finish proofing gently as it heats. Add 3 to 4 minutes to the steaming time.
• Use milk and a low-protein flour for the whitest buns. Unbleached all-purpose gives a slightly creamy color, which is normal.
• Keep shaped buns covered while you work. A dried surface turns into a rough, cracked skin in the steamer.

Substitutions

Low-protein flour

Replace 30 g of all-purpose with cornstarch for a softer, whiter bun if you only have standard all-purpose flour.

Baking powder

Leave it out and add 10 minutes to the second proof. The buns will be a bit less fluffy but still soft.

Neutral oil

Melted lard or shortening gives a slightly richer, more tender bun, which is a common choice in traditional recipes.

Variations

Filled round buns

Roll each piece to a 10 cm circle with thinner edges, place 1 heaped tablespoon of cooled cooked filling in the center, pleat closed and steam for 12 to 14 minutes.

Pandan bao

Replace 30 ml of the liquid with pandan extract diluted in water for green, fragrant buns.

Troubleshooting

Buns wrinkled or collapsed

They were overproofed, the heat was too high, or the lid came off too soon. Shorten the second proof, steam at medium and wait 5 minutes before uncovering.

Yellow spots on the surface

Undissolved baking powder or water dripping from the lid. Whisk the dry ingredients thoroughly and wrap the lid in a towel.

Dense, heavy texture

The dough was underproofed or kneaded too little. Knead until smooth and let the shaped buns rise until visibly puffy before steaming.

Folded buns stuck shut

Not enough oil on the inside surface. Brush it fully to the edges, or lay a small strip of parchment inside each fold.

Storage

Cool steamed buns completely, then refrigerate in a sealed bag for up to 3 days or freeze for up to 2 months. Resteam from chilled for 3 to 4 minutes or from frozen for 8 to 10 minutes; do not thaw first.