Put bread flour in a bowl. Mix in the ½ cup of sugar and the salt.
In a small bowl or large measuring cup, add the 1 ½ cups of warm water. Mix in the 1 tablespoon of sugar. Sprinkle the yeast on top and wait 8 minutes. The yeast mixture should be foamy.
Briefly mix the yeast mixture, then mix it into the flour mixture.
Mix in the eggs and oil.
Add the remaining 1 cup warm water, and knead the dough for about 10 minutes.
Divide the dough into four parts. These will make 4 challahs.
Take one part. Separate it into four pieces. Take each piece and roll it between your hands until it is a long strand. Attach the four strands together at one end by squeezing the ends together (see picture).
↑Weight conversions from USDA National Nutrient Database. Original recipe text and ingredient order preserved. Used "1/2 cup plus 1 tbsp" for sugar conversion. Active dry yeast, large eggs, and soybean oil presumed. Density adjustment not applied to warm water.
↑This excessive amount of yeast will result in a strong yeast flavor. To reduce this flavor, it is recommend to use no more than 0.75% instant dry yeast which means about 9.24 g, or about 2 1/4 teaspoons, although you can expect fermentation time to increase slightly. Osmotolerant yeast may be desired for optimum results.