The San Antonio Mexican bakery's shelves are heavy with panaderia offerings familiar to denizens of the western U.S.: fruit-filled empanadas, shell-shaped conchas and torta-worthy bolillos. But transplants from the American South will gravitate toward the homey pecan-paved tarts, miniature relatives of the familiar holiday pies lovingly baked by grandmothers from Atlanta to Austin. And these are tarts guaranteed to make any granny swoon: The aroma of brown sugar and sweet, toasted pecans is overwhelming from the moment you open the paper bag. In the right hands, the alchemy of butter, sugar and pecans makes for a magical dessert that translates to bliss in any language.