Steaming foods preserves their natural flavors, moistens them, restores them. Leftover foods that have shrunk expand when exposed to penetrating steam, breads become fresh, and dried-out cooked rice becomes moist and fluffy.
Steaming is, in every respect, a restorative process that makes foods glisten. It is a historic method of Chinese cooking that stretches back through the centuries to when there were no ovens and all food had to be cooked on the top of a brick stove over a wood fire, with woks as the steaming vessels.