Published March 1, 2012. From Cook's Illustrated.
To rid this bread of its dense crumb, leaky filling, and huge gaps, we had to engineer a lofty dough and a sticky filling—and then find the right shaping method.
Most versions are either austere white sandwich loaves rolled up with a bare sprinkle of cinnamon and sugar or are overly sweet breads ruined by gobs of filling oozing from the cracks.
Our ideal is in the style of Japanese sandwich bread called shokupan: fluffy, delicate, studded with plump raisins and laced with a substantial swirl of gooey cinnamon sugar.
Shokupan’s hallmark lift and airy texture come from considerable gluten, the network of proteins that builds structure. To achieve this, Japanese bakers use hard to find high-gluten flour. We’d have to do our best with a more accessible type of flour—and whatever tricks we could come up with to aid in gluten development.
One of those tricks was incorporating more air into the bread. Oxygen is the driving force behind gluten development; the more oxygen the dough gets the stronger the gluten network. To this end, we increased the kneading time and introduced two sets of “folds” into the process. We also waited until we were almost done kneading to add our recipe’s butter, an ingredient that inhibits gluten formation. These measures gave us a gorgeously lofty loaf that would serve as the perfect counterpoint for our gooey cinnamon swirl.
We thought that perfecting a thick cinnamon swirl would be the easy part of making the bread—until each test with it turned out leaky loaves that spewed molten cinnamon sugar from its crevices. What we needed was a way to encourage binding between the swirl and the dough. Instead of adding extra ingredients, we reworked the ones we already had. Swapping granulated sugar for confectioners’ and upping the amount of cinnamon worked perfectly. When powdery confectioners’ sugar absorbs water from the dough, it forms a sticky paste. This paste is then thickened by the cornstarch in the sugar and the cinnamon.
This markedly improved the filling and binding connection, but we took one more measure to ensure that the steam that formed inside the dough as it cooked didn’t run the risk of blowing out the bread. Forming our loaf into a three-pronged Russian braid completely eliminated gapping and leaking because it allowed trapped gas to escape.list of recipes