Ghulam Bombaywala sells bagels in Houston. Demetrios dishes up pizza in Connecticut. The Wangs serve tacos in Los Angeles. How ethnicity has influenced American eating habits--and thus, the make-up and direction of the American cultural mainstream--is the story told in We Are What We Eat . It is a complex tale of ethnic mingling and borrowing, of entrepreneurship and connoisseurship, of food as a social and political symbol and weapon--and a thoroughly...