Recognition usually comes to me out of the blue. Today I'm listening to ancient records on WFMU's "Antique Phonograph Music Program" for Jan 13. The announcer intros a song from 1924 he calls "Beautiful Heaven." It's a Latin tinged orchestra instrumental, which suddenly leads into the familiar chorus of "Ay, Yi, Yi, Yi!" Hey! I know this tune. Some searching around the title finally informs me that yes, it is a Mexican folk tune, originally titled "Cielito Lindo."
As the Wikipedia article I linked to will inform you younger kids, this tune is better known to us Anglos of a certain age as the "Frito Bandito" song. Hope I can remember at least its proper title when I hear it again.