"Challah, the delicious and beautiful braided bread traditionally served at the weekly Friday night Jewish Sabbath meal, is made more wholesome and nutritious with the addition of whole wheat and sweetened with honey. This slow-rise recipe is designed for flexibility, so split-second timing isn't necessary. This is a wonderful bread for a first-time breadmaker."
In a large bowl, mix yeast, warm water and 1 cup of the flour into a thin batter. In 30 minutes or so, this should have bubbles and froth from the yeast developing. This is now called the sponge.
Add the oil, honey, eggs and salt to the sponge. At this point, you can also add customizing ingredients like a teaspoon of vanilla, 1/2 cup sunflower or flax seeds, or raisins.
Add the flours, alternating between the whole wheat and bread flour, one cup at a time, until it’s too hard to stir more flour in. Generously flour a work surface, and turn the dough out of the bowl. Continue to work the dough with your hands, kneading and adding flour until the dough is elastic and smooth. Form the dough into a rough ball. Wipe any clinging dough/flour out of the big bowl, and pour a tablespoon or two of oil into it. Coat the dough ball with the oil, and leave it in the bowl, covered loosely with a plastic bag. Let rise 6-8 hours, or overnight if more convenient. The dough should rise until it’s double the original size. It is ready for the next stage when you can poke it with a finger and it stays dented.
If you need to slow it down—say, you make the dough on Wednesday evening, but want to bake it on Thursday evening— after you’ve placed the dough ball in the bowl, refrigerate it until Thursday morning. This should the yeast’s growth so that you can leave it out on the counter until it’s ready for the next stage in late afternoon, early evening.
Punch down the risen dough. It’ll deflate significantly. Knead it briefly to remove some of the bubbles. Divide the dough into 3 evenly sized pieces. Divide each third into 3 or 4 evenly-sized pieces. Form 3 or 4 of the smaller pieces into ropes that are thicker in the middle and taper at the ends. The dough will be pretty springy and elastic, so the ropes will have to rest a few minutes and rolled some more, or they try to spring back into balls.
Braid the strands into a loaf. Pinch the ends together and tuck underneath. Transfer the loaf to a parchment paper-covered baking sheet. Repeat with next 3-4 strands of dough. 3 loaves should fit on the sheet.
Let loaves rise until about double in size. This should only take about 45-minutes to an hour. Preheat the oven to 350 degrees. Beat an egg with a little water. Brush risen loaves with the egg mixture. If desired, sprinkle with sesame or poppy seeds. Place loaves in center of the oven. Bake for about 40 minutes. Loaves should rise significantly, and become deep golden brown. When done, loaves should sound hollow when thumped on the bottom (pan) side. Cool on a rack before serving.