I made this today and it turned out very well.
Challah
2 teaspoons (6 grams/0.2 ounce) instant yeast
About 3 1/2 cups (475 grams/16.8 ounces) unbleached all-purpose flour
1/4 cup (60 grams/2 ounces) warm water
3 large eggs, plus 1 for glazing
1 1/2 teaspoons (8 grams/0.3 ounce) table salt
1/4 cup (55 grams/1.9 ounces) vegetable oil
1/4 cup (85 grams/3 ounces) mild honey or 1/3 cup (70 grams/2.4 ounces) granulated sugar
In a large bowl, whisk together the yeast and 1/4 cup (30 grams/1.1 ounces) of the flour, then whisk in the warm water until smooth. Let the yeast slurry stand uncovered for 10 to 20 minutes, or until it begins to ferment and puff up slightly.
Whisk the 3 eggs, salt, oil, and honey (measure the oil first, then use the same cup for measuring the honey — the oil will coat the cup and let the honey just slip right out) or sugar into the puffed yeast slurry until the eggs are well incorporated and the salt has dissolved. With your hands or a wooden spoon, stir in the remaining 3 1/4 cups (445 grams/15.7 ounces) flour all at once. When the mixture is a shaggy ball, scrape it out onto your work surface and knead it until smooth, no more than 5 minutes. (Soak the mixing bowl in hot water now to clean and warm it for fermenting the dough.) This dough is very firm and should feel almost like modeling clay. If the dough is too firm to knead easily, add a tablespoon or two of water to it; if it seems too wet, add a few tablespoons flour.
The dough should feel smooth and very firm but be easy to knead.
Place the dough in the warm cleaned bowl and cover it with plastic wrap. Let the dough ferment until it has at least doubled in bulk, about 2 hours, depending on the temperature in your kitchen.
Line a large baking sheet with parchment paper or oil it. Divide the dough into three portions. Roll each portion into a log about 14 inches long. Pinch one end of the logs together and braid them together pinching the final ends together.
Cover the loaf well with plastic wrap. (At this point, it can be refrigerated for up to 24 hours.) Let it proof until tripled in size, about 2 hours (or up to 3 hours if it was refrigerated).
Meanwhile, 30 minutes before baking, arrange the oven rack in the lower portions of the oven. Preheat the oven to 325°F (160°C). Beat the remaining egg with a pinch of salt for glazing the breads.
When the loaf has tripled and does not push back when gently pressed with your finger but remain indented, brush it with the remaining egg, beaten. Bake for 35 to 45 minutes, until very well browned. After the first 20 minutes of baking, rotate the baking sheet so the bread will brown evenly. If the loaf is browning too quickly, tent it with foil. The loaf should have a hollow sound when tapped on the bottom. When the loaf is done, remove from the oven and let cool on a rack.