Lately, I've had burgers on the brain. Aside from my post of August 4, I recently I wrote about Mexican street hamburgers for a web site called Culinary Backstreets. Some readers already found it and written to me, but for those of you who have not, here is the link: http://www.culinarybackstreets.com/mexico-city/2014/hamburguesas-la-parrilla/. As I wrote, I didn't come to Mexico City to eat hamburgers. But when a savvy chilanga introduced me to these charcoal-grilled babies, I realized that burgers could be Mexican, too. They are a guilty pleasure for me.