In another thread, several posters said that Cajun or Ethiopian food can't be made well outside their home regions.
This is a canard I've heard often about any number of cuisines, and I think it's untrue.
Yes, there are certain unavailable ingredients upon which certain dishes rely. E.g. good luck finding richly flavored eggs to make a proper Spanish tortilla (which absolutely relies on those superb orangey Spanish eggs). But most ingredients ARE available...or at least reasonable imitations (e.g. spinach for some of those weird Indian greens). And there is no cuisine in the world whose entirety is based on ingredients unavailable and unreplicable here (well...Inuit whale blubber an exception, though I think those guys have vastly widened their diet in last decades).
There's nothing about Cajun food that pins it more firmly to Cajun country than Portuguese is pinned to Portugal or Shanghai to Shanghai. And you can eat both those two really well all over.
Of course, if you really really know a cuisine, it becomes harder and harder to enjoy in-absentia versions. There are really good representations of cuisines being made in distant locales, but the dead-on perfect recreation is pretty rare. More often, there's a melding born of compromise and impediment which talented cooks manage to make delicious.
But such niggles still don't explain why all the Cajun food within 200 miles of NYC pretty much sucks (exceptions, both dead: Miss Ellie's Cafe in Smithtown, Long Island, and the catfish po' boys at Savannah Club before they declined and then closed).
This thread could expand into flame wars over "What IS authenticity", but I'd really ask that it not. I'm just talking about, like, some gumbo or jambalaya that evokes LA, that's all. Needn't split philosophical hairs! :)