[Note: We split this thread from the Boston board at: http://chowhound.chow.com/topics/7342... -- The Chowhound Team]
"Authenticity" and "tasty" are two different things. I can't speak about Chinese food, not having the necessary experience (just the enthusiasm), but "authentic" Indian food in the U.S. is a complicated proposition. Just getting the food to be more spicy does not make it more authentic. It simply means the staff have identified you as one of those Internet crazies who want more chillies in everything. Much genuine Indian food requires long, slow cooking. The kitchen cannot make you authentic food on demand. They can ratchet up the spice level, and it may make the food more tasty, but it does not make it authentic.
Consider the biryani. More specifically, consider mine. I made one yesterday that required four hours of the meat cooking at the gentlest possible heat, then 20 minutes of layering of rice, meat, caramelized onions, and saffron-infused milk, then 45 minutes of the layers and flavors coming together in a tightly sealed dish in an oven at 275F. No restaurant can do this authentically on demand -- especially if they have shrimp, lamb, chicken, and vegetarian biryanis all on the menu. They might produce a tasty combination of meat/seafood/vegetables and rice, but it won't be authentic.
And don't get me started on vindaloo. What's served in restaurants in the U.S. has no relationship with the authentic original Goan dish. (The only places I've had true(ish) vindaloo here, outside my kitchen, have been at Spice Market in NYC and, bizarrely, for a while at the Oxford Spa in Cambridge whose owners at the time had stumbled upon a good recipe. Neither version was vinegary enough or fatty-porky enough to be 100% true, but they were closer than conventional restaurant versions.) You may like the way "chicken vindaloo" tastes at some Indian restaurant, and that's totally legit., but the dish won't be authentic.