One of my desert island books is Marilyn Tausend's Cocina de la Familia. My copy is literally falling apart. She's also worked on several other classics and givesd culinary tours of Mexico. Regarding my post on tequesquite, Marilyn wrote:
While, tequesquite does come from the highland lakes in and around
Mexico's central valley, it is a mineral salt, not an algae, composed
of sodium carbonate and chloride. It is used, and has been used since
pre-hispanic times as a leavening agent for tamales, and to soften
dried beans or corn. I often use it when I cook my nopales as it seems
to keep them a brighter green. You can buy it in most Mexican markets
in the United States, and of course, in the mercados of Mexico and
dilute it with water, boil it, and then let it set until the minerals
drop to the bottom, then use the greyish clear water for cooking.
But back to pond scum, or algae,(Spirulina geitleri) or Tecuilayl
was an important source of food for the Mexica's (Aztecs) and the other
indigeneous groups that lived around the lakes, where it was skimmed
off, slightly dried in the sun, and then formed into small cakes and
dried again. It was very valuable as a source of trade, and the those
first Spaniards to eat it said "it tastes like cheese...but less
pleasing and with a certain taste of mud.
When I asked what's new with her, she mentioned that in addition to a new book she's working on, she's organizing a once-in-a-lifetime cooking experience:
We have a few spots for either culinary
professionals or extremely experienced home chefs cooking with Diana Kennedy at
her home in Zitacuaro, Michoacan. (More on my website:marilyntausend.com).
It runs from July 19-25, and starts and ends in Mexico City, and the $3250 cost
includes lodging, the transportation to Michoacan, the classes, and at least
two meals a day.