Bread making is an art as well as a science, and may take a while until you get the kind of challah you want. It takes more time than most recipes on this site.
My friend Miriam Kresh of Israeli Kitchen suggests using less yeast in baking, leading to a lighter, airier bread with less yeasty taste. But it involves a longer rising time. She helped me work out the recipe below.
A sponge contains all of the yeast and liquids, and about two-thirds of the flour called for in the recipe. It allows you to use less yeast, compensated for by a longer rising time. This means that you end up with an airier dough with more flour taste than yeast. Sometimes it consists of only the water, yeast, and the majority of the flour.
