Khao Sarn is one of the best Thai restaurants in the immediate Boston area- and it is one of the few that can bill itself as "authentic Thai cuisine". The dishes here are just wonderful. If you don't like spicy food, be aware that many dishes are not for the faint of heart. I tried one of their curries on my last visit and had to ask for multiple glasses of water--- which the friendly service bought without batting an eye.
This restaurant is always busy, but the service is always great in spite of this. The prices are higher than most Thai restaurants, but worth it for the culinary experience.
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