I had been to Bahar a few months ago, on recommendations from this board and liked it a lot. I went back this weekend and now I think that it is the best Afghan in NYC. It's on Coney Island Avenue in Brooklyn, near Newkirk Avenue (a few blocks from the Newkirk stop on the Q line).
We started off with Boulanee Kadu, which are pumpkin fritters that you dip in a yogurt sauce, and Aushak, a scallion dumlping. Both were very tasty, but the Boulanee Kadu really rocks - sweet but not overly sweet, contrasting terrifically with the dipping sauce. For a main course, we got chicken fesenjen, which is chicken in a pomegranite sauce - delicious - and ashti gooshti, which is a pasta dish with meat and a minty yogurt.
This place seemed pretty empty on a Saturday night - so go check it out!