In a cup, dissolve yeast in 1/2 cup warm water; set aside. In a large bowl, combine hot water, sugar, salt, oil and 3 cups flour; stir well. Stir in yeast mixture.
Add remaining flour and stir well with a heavy spoon. Leave spoon in the dough; allow dough to rest 10 minutes. Stir; let dough rest another 10 minutes. Repeat this process 3 more times, making 5 times in all. Turn dough onto a lightly floured board. Knead just enough to coat dough with flour; divide dough into 5 equal balls.
Roll out each ball into a 5-inch by 8-inch rectangle; roll up lengthwise, pinching together seams. Pinch and form ends to resemble the end of a bone.
Place loaves seam-side down on 2 greased baking sheets, allowing room for both to rise. Cover; let rise in a warm place for 30 minutes, or until double in bulk.
Brush with egg white.
Bake at 400 degrees for about 30 minutes, or until crusty and golden.