Combine yeast, water, and sugar in large mixing bowl and let stand 10 minutes or until bubbly. Add salt, vegetable oil, and egg yolk (set white aside for later) and combine. Add 3 c. flour and mix well until combined. Add enough remaining flour to make a soft dough that barely sticks to your finger. I ended up adding a total of about 4 1/2 cups. I used 2 and 3/4 cup all purpose and 1 and 3/4 cup whole wheat flour. Knead, either by hand or in mixer with dough hook attachment for another 2-3 minutes. Cover and allow to rise 1 hour 45 minutes. A quicker way for dough to rise would be to allow oven to heat up to 200 degrees F and then turn it off. Place covered dough into oven for about 1 hour, or until doubled.
Punch down dough. Spray a cookie sheet with non-stick cooking spray. For a loaf of bread, shape into loaf and place on greased cookie sheet. For buns or hoagies, divide equally into equal pieces and shape as desired. I was able to make 20 sandwich rolls, I could have done 24 if I had done some a little smaller.
It's okay if they touch (or will touch after having risen). Cover and allow to rise another 1 1/4-1 1/2 hours or until doubled. (I used my oven for this rise too.) If they look like they are getting to big, go ahead and put them in the oven to bake, you don't want them to collapse.
Preheat oven to 375. Mix egg white with water and brush over dough. Bake for 10 minutes and repeat brushing the dough with the egg wash.
Bake an additional 6-10 minutes or until bread is golden brown.