Coffee and connections

It sounds delicious:
[I]magine a short glass with a hard dose of sweetened condensed milk, the color of ivory and the texture of hot fudge. The glass wears a metal top hat, a filter with grounds and water, which dribbles in drops of thick coffee, crude-oil black and nearly as bitter. They sit, stacked in two layers, until you take a spoon and give it a turn. For a moment, the coffee and milk swirl around each other, hesitating before coming together, a phenomenon smarter people than me call sensitive chaos. You take a sip, and the sweetness hits first, full and rich. Then your mouth dries a bit, like the tide pulling back, and coffee leaves a mellow bitterness. You take another sip, and suddenly everything is right with the world. [...]

And, like every culture and every cuisine, it keeps changing. Nearly every time I order one in the U.S., someone reaches for an orange tin of Café du Monde, the coffee-and-chicory blend that's the pride of New Orleans. (Well, the beignets -- dough fried 'til pillowy and buried in powdered sugar -- are probably what they're really proud of, but you can't pack those in tins.) The Café du Monde is so ubiquitous that I thought it had somehow traveled from Louisiana, through some Francophone space-time continuum, to become popular in Vietnam. My confusion got even deeper when I actually went to Café du Monde and saw that all the servers were Vietnamese.