I have been reading a lot about authenticity recently. It has made me look at the food of New Orleans and Louisiana to try to define what may be authentic about it. I think that after many bowls of gumbo and many people's versions of red beans and rice, I have come to a conclusion. This is likely to be an unpopular notion.
When we are familiar with the cuisine, I think that we consider authentic to be what we know. That means what we remember from early family life - what Mom or Dad or Aunt Jane served - defines authenticity. So if my mother took shortcuts and used prepackaged shortcuts or added cream of mushroom soup to her oyster bisque (she didn't), I might find that to be authentic. The younger person may say, never, it is only authentic with cream and homemade stock. But neither of us was around in 1900 when oyster bisque was made in some other way to make it authentic.
So if we have no early memory of food to benchmark authenticity how can we do it? I think that if local people eat the food, even as it is evolving, then it is authentic. Yes, food can be made the way that it was in 1875. But just because it is historically accurate doesn't make it any more authentic than the way we make it in 2009. Food changes: we begin to add garlic, we begin to omit blood sausage, we add wine, we experiment. As food evolves it remains authentic because it is still eaten and identified by the people in the area.
No cuisine remains alive if it is static, so historically accurate does not define authentic - eaters do. I have eaten many version of Salade Nicoise in the US and in France. In Nice this salad is served tossed in a bowl or on a plate. It is not a composed salad, but a tossed salad. As I traveled west along the coast in France, I was in Provence when ordering the Salade Nicoise was composed. I would venture to say that dispite the fact that I know this as a composed salad, that what I ate in Nice was authentic.