Consider the muffuletta, another iconic New Orleans sandwich. And, like the poor boy/po-boy/po' boy, another local controversy as to both its origin and pronunciation.
Said to have been created in 1906 by Salvator Lupo, owner of Central Grocery (still in operation today) , versions of the large, round loaf had been known in Sicily for centuries. The bread, not the sandwich.
The sandwich constructed on the round sesame seed-encrusted loaf is composed of layers of thinly-sliced salami, ham, mortadella, and provolone cheese which are then topped with an olive salad consisting of green olives and finely chopped giardiniera seasoned with oregano and garlic, all drizzled in extra virgin olive oil.
Whether it's next baked toasty hot or left room temp to serve is a matter of preference. Some believe the sandwich must always first be pressed for a period of time under a weight in either case.
When it comes to purchasing, you can pretty much count on being able to buy a half sandwich as well as a whole anywhere you go.
Some writers bristle at the notion of the hollowing out of a portion of the crumb of the bread before constructing the sandwich. Some sellers do it; some don't. But it makes sense to do so. The bread isn't really the star here, and it can make the difference between being able to consume a quarter, a half, or in some cases, a whole sandwich in a sitting.
Really, if you think about it, the etymology of the word muffuletta is from the Italian muffoletta or "little muff", a diminution of muffola or "muff", and which suggests a pocket.
As to pronunciation, you hear it basically two ways: "muffa-LET-a" or "muffa-LOTTA". The purist in town, however, might argue "MOO-fa-LET-a" is correct. It is never, however, shortened to just "muff".