B&B By is one of the oldest premixed cocktails. In the 1930s, during Prohibition in the United States, a barman at Club 21 in Manhattan came up with the idea of mixing brandy with Bénédictine.

In 1937, Le Palais Bénédictine decided to produce this by blending 60% Bénédictine with 40% fine French Brandy, allowing the flavors to rest and harmonize in small, vintage French oak barrels that have previously been used to age only the finest cognacs.