Boker's bitters

Also known as Bogart's Bitters is a defunct proprietary New York-based digestive bitters brand of presumed cardamom character called for in 19th century cocktail guides as aromatic bitters. There is no evidence of manufacture after Prohibition, or indeed after the advent of the 20th century. Bogart's Bitters is a corruption of Boker's Bitters. The product is no longer available, though it was originally produced and sold in United States. It is no longer manufactured.

Substitutes

 * Angostura Bitters
 * Peychaud's Bitters
 * any other aromatic bitters