The June 2012 issue of Smithsonian magazine has yet another Andrew 
Beahrs food article with twain references:
http://www.smithsonianmag.com/arts-culture/The-Decades-Long-Comeback-of-Mark-Twains-Favorite-Food.html


See also 
http://www.amazon.com/Twains-Feast-Searching-Americas-Footsteps/dp/1594202591

Tony
<http://www.huffingtonpost.com/andrew-beahrs/mark-twain-favorite-foods-comeback_b_737209.html#s144341&title=Oysters_in_San>