By Ron Bechtol
"Flour or corn?" It's a question that might draw quizzical looks in Sheboygan, but no San Antonian would give it a second thought. For all of its ubiquity, though, the query is a come-lately one in the history of the tortilla: Cortez' troops were not faced with the dilemma on their first visit to the markets of Tenochtitlan. Corn tortillas (and tamales) were established staples and had been for centuries. The flour tortilla wouldn't appear until several generations of Spanish colonizers had firmly established the presence of wheat - mostly in northern Mexico. Used then as now as a simple wrapper for foods - a spoon and fork all in one - the tortilla is an immutable symbol of Mexican cuisine.
Adding to its immutability is the tortilla's preparation: Except for some inevitable mechanization, it hasn't changed in essence since pre-Hispanic times. Corn is still dried, soaked in lime, boiled to loosen the skin, ground into a paste called masa, and formed into disks and cooked on a comal, or griddle.