Grease pans, mix together yeast, 11/2 tablespoons sugar and 1 cup warm water. Let sit for 5-10 minutes. Add remaining water, sugar, oil, salt and flour to the yeast mixture. Mix for 12 minutes, or knead by hand.
Place dough in a large bowl, cover with a drop of oil and cover. Let rise for 1 hour.
Form 6-7 medium large challahs. Let rise for another 30 minutes.
Preaheat oven to 350; baked 30-40 minutes. *
I bake at 325 for the same times as we like the challah a little moister.
Contributed by Amy Greenbaum Jacobs.