I don't claim to be any sort of expert on Indian cuisine, and I cannot speak convincingly to authenticity of any that I've had, but Punjab Palace in Allston (a western neighborhood of Boston, MA) is the second best I've ever had, and the best in the USA. Located just a block from my friend Joe's apartment, he goes there pretty often, and it's not hard to understand why. The staple of our meals there is the naan, which is always delicious (seriously, have you EVER had bad naan?), but especially so at Punjab Palace, where I've had both the plain and garlic versions. I prefer the plain, because it tends to work better for use in seizing the small, delicious chunks of whatever meat I've ordered and the basmati rice that comes with it. Having learned from a close friend of Indian ancestry that the primary purpose of naan or any of its related flat breads is to be used to pick up the rest of the food rather than simply using one's fingers, I actually find that this is also the best way to enjoy the full range of flavors that are present in the cuisine. For example, my favorite dishes are vindaloo (a curry dish) and shahi korma (a yogurt, cream and nut sauce), both of which have some spice; the buttery naan creates a perfect contrast with the spice, and also a chewiness that contrasts nicely with the delicate, tender lamb and goat which tend to be my favorite options. So, while I cannot say whether this is legitimately authentic (though judging by the number of Indians I've seen eating there, I suspect it is), it is damn good, and if you're in the area, check it out.
As an added treat, after you leave there you should take the extremely short trip across the street to Sunset Grill and Tap (or its upstairs, Big City), where there are over 110 taps and nearly 400 bottled varieties of beer available.
Check us out on Facebook!