Why do recipes call for unsalted butter--and salt? What is a microwave, actually? Are smoked foods raw or cooked? Robert L. Wolke's enlightening and entertaining What Einstein Told His Cook offers answers to these and 127 other questions about everyday kitchen phenomena. Using humor (dubious puns included), Wolke, a bona fide chemistry professor and syndicated Washington Post columnist, has found a way to make his explanations clear and accessible to all: in short, fun.