Marion Cunningham, considered the doyenne of American home cooking and mentor and confidante to many of the nation's top chefs, died of complications from Alzheimer's disease Wednesday morning at John Muir Medical Center in Walnut Creek {CA.} She was 90.

She is perhaps best known as the woman who rewrote "The Fannie Farmer Cookbook." It was published in 1979 and became one of the nation's best-selling cookbooks. That was followed by "The Fannie Farmer Baking Book," "Learning to Cook," "The Breakfast Book" and several others.

Mrs. Cunningham, a longtime Walnut Creek resident, grew up in the kitchen at her Italian grandmother's knee, but it wasn't until she was 50, pushed by a friend to take a cooking class with the master American cook James Beard, that she started a professional food career. Beard eventually tapped her as his assistant, which led her to a career of teaching people to cook through classes and books.