B & B is the trade name (registered in the US) of a combination ("perfect harmony") of benedictine and cognac. This 40 proof liqueur is made and bottled by Bénédictine S.A. (Fécamp), France.
A wonderful after dinner drink, B & B should be served straight up, chilled, in a liqueur glass (not a snifter — its nose is quite sharp) and sipped slowly.
One can also enjoy B & B over ice, in coffee with whipped cream, or over ice cream.
Sweet and sharp, almost tangy, and wonderfully warming, some people love B & B, and some people hate it. There are few who try it and fall in between those extremes.