Whether you go yellow or white, sweet or savory, grits are a Southern food staple now popping up on menus all over the country. Food writer Erin Byers Murray goes deep in Grits: A Cultural and Culinary Journey Through the South , talking with growers, millers and chefs to understand the origins and evolution of grits. Along the way, she examines how race, gender and politics simmer in the significance of grits.