I did a little research on Amy Tan.  A few highlights:

As you might already have guessed, the story told in "The Kitchen God's Wife" is largely based on her mother's experiences.  Daisy was forced to leave three daughters behind when she left China.  She escaped on the last boat to leave Shanghai before the Communist takeover.  

Amy's father was also a Chinese immigrant.  John Tan was an electrical engineer and Baptist minister.  He and Amy's oldest brother died of brain tumors, less than a year apart, when Amy was about 15.  Daisy took her remaining children to Switzerland where Amy graduated from high school before the family returned to San Francisco. 

Amy and Daisy went to China in 1987.  They were able to find at least one of the daughters Daisy had left behind.  It was during this trip that Amy became immersed in her Chinese heritage.  Stories brought back from that journey are the basis of many of her stories.  

You can go to the following website for more information:

http://www.achievement.org/autodoc/page/tan0pro-1

Amy Tan's own website is also an interesting place to go for a visit:

http://www.amytan.net/

Amy Tan is part of a rock band made up of writers called "The Rock Bottom Remainders."  You were probably aware of this.  Other  members include Matt Groening, Dave Barry, Mitch Albom, and Stephen King.  

Something interesting that I didn't know:  Amy Tan suffers from the effects of Lyme Disease.  She recounts this experience on her website.  It's worth reading!

We must have our official book club meeting soon!