I will second Bar Tano. This was the first place that popped into my head when I read the OP.

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Bar Tano
457 3rd Ave, Brooklyn, NY 11215

Another vote for Framboise. My parents (live on SI) have used them for years. The food is very good and doesn't seem like the standard boring caterer food.

They will send a chef to cook alot of the food on-site if you like.