A short time ago there were some discussions of what constituted "Authentic" in several threads on this forum. I had hoped that the person most in pursuit of authentic would have taken the ball and run with it, but no such luck.
I've often thought that authentic is a snapshot of a time and place as well as conditions and ingredients. I think of Italian food using lots of tomatoes and Thai food as laced with peppers. Both tomatoes and peppers are New World plants, so at what point did they become "Authentic"?
Anyway, I was watching "The Search For General Tso" on Netflix the other day and thoroughly enjoyed it. It touched on what is authentic Chinese cuisine and basically the conclusion I drew is that authentic is at the end of he rainbow. It's a constantly moving and evolving target. The documentary covered a lot of the history of Chinese food in America. I found it interesting that the authority on Chinese food in New York is a Jewish man. There are supposedly about 50,000 Chinese restaurants in the US. There was a Chinese man who claims to have eaten at 6,000 of them.
The conclusion I drew from the movie is that most food is true to the original dish for only a short time and then morphs into something suitable for the local market.
The movie is very entertaining and is worth an hour and a half of your time. One caveat; ordering take out General Tso's Chicken to eat while watching the moving will not enhance the experience. Trust me on that.