1. In the bowl of a mixer, dissolve yeast in warm water. Add one tablespoon sugar and let stand until foamy, about 10 minutes. Add soy milk, oil, remaining three tablespoons sugar, and egg.
2. Add three-and-a-half cups flour, dough enhancer if using, and salt on top. Mix together until a soft dough forms, adding the remainder of the flour. Knead for about five to 10 minutes until smooth and elastic.
3. Place dough in a large greased bowl, covered, or in a loosely tied garbage bag. Let rise until doubled, one to one-and-a-half hours.