When Hugo Ortega was a small boy shining shoes and selling freshly made flan in the marketplace in Mexico City, no doubt it never crossed his mind that one day he would be teaching Americans to cook the foods of his homeland. But that was a long time ago, and now he is one of the most admired chefs in Texas, the co-owner of Hugo’s, in Houston, as well as Backstreet Café, in the same city. Earlier this year, Ortega, with his brother, pastry chef Ruben Ortega,  published his first cookbook, Hugo Ortega’s Street Food of Mexico. It was excerpted in Texas Monthly in August.   Next week, he will be in Austin teaching at Central Market (Thursday, October 25, at 6:30 p.m.) and doing a cooking demo at the Texas Book Festival (Saturday, October 27, at 10 a.m.—moderated by yours truly, in the cooking tent). Happily, there are still seats available for the cooking class (they’re $60), and the Book Festival demo is free and open to the public on a first come, first served basis. The class menu takes you well beyond tacos and tostadas to include fascinating interior dishes like tlacoyos (masa cakes stuffed with refried beans and topped with mushrooms); garnaches with tinga de conejo (sweet potato masa cakes with savory rabbit stew); aguachile (shrimp marinated in lime juice—think of it as Mexican sashimi); and gaznates (sweet fritters with meringue filling). Copies of the book, published by Bright Sky Press, will be available for sale. ¡Buen provecho!