Ok...I got it:
I found the answer way down the end of the page for "New Orleans" in Wikipedia:
The city's several nicknames are illustrative:
<< * Crescent City alludes to the course of the Mississippi River around and through the city.>>
Another popular nickname, The Big Easy, is attributed to Betty Guillaud according to this website, The Big Easy Dictionary:
This is [a] euphemism for New Orleans, like the "Crescent City," that is attributed to Betty Guillaud, a gossip columnist for the Times Picayune, in the '70s as a term of endearment and an answer to the then I Love New York City hype. If it's the "Big Apple" then New Orleans is the "Big Easy," where everything is slower, simpler and easy-going.