These buns are a twist on the classic Chinese egg custard buns (奶黃包, nǎihuángbāo). They still have the creamy custard and the fluffy steamed bun, but I added pumpkin and fall spices to both the filling and the dough to create a pumpkin spice version. Notes on ingredient substitutions and the science behind the custard filling, dough, and steaming process follow the recipe!
Bread dough doesn’t have to be baked. In Chinese cooking, for example, it’s often steamed to make buns. Commercial western-style bakeries also use steam to bake larger loaves with shinier, crisper crusts, an effect home cooks replicate with Dutch ovens. In this post, we’ll compare three methods of cooking bread dough using 花卷 (huājuǎn, literally “flower roll”), a type of Chinese steamed bun speckled with scallions. We’ll compare the traditional steaming method to baking and to baking with steam.
In the last post, we discussed the molecular details of starch: what it is, where it comes from, and how it changes with water and heat. Today, we’ll apply those concepts to baked goods with a focus on the starch in wheat flour. Although flour is often noted for its gluten, it actually contains 68–75% starch. So when we consider the chemistry of any baked good that contains flour, be it cake, bread, or cookies, starch always plays a role. And in foods cooked in steam or boiling water, starch helps create textures as diverse as soft skins on steamed buns, chewy crusts on bagels, and crisp shells of choux pastry.
In the last few posts, we’ve been talking about leavening gases, which give our baked goods volume and tenderness. Last time, we focused on baking soda and baking powder, which quickly produce carbon dioxide through chemical reactions. In this post, we’ll take a closer look at yeast. We’ll describe what yeast are, how they leaven, and what to consider when working with them.