The original Irish coffee was invented and named by Joe Sheridan, a head chef in Foynes, County Limerick. It was conceived after a group of American passengers disembarked from a Pan Am flying boat on a miserable winter evening in the 1940s. Sheridan added whiskey to the coffee to warm the passengers. After the passengers asked if they were being served Brazilian coffee, Sheridan told them it was "Irish coffee".

Stanton Delaplane, a travel writer for the San Francisco Chronicle, brought Irish coffee to the United States after drinking it at Shannon Airport, when he worked with the Buena Vista Cafe in San Francisco to start serving it on November 10, 1952, and worked with the bar owners Jack Koeppler and George Freeberg to recreate the Irish method for floating the cream on top of the coffee, sampling the drink one night until he nearly passed out. The group also sought help from the city's then mayor, George Christopher, who owned a dairy and suggested that cream aged at least 48 hours would be more apt to float. Delaplane popularized the drink by mentioning it frequently in his travel column, which was widely read throughout America. In later years, after the Buena Vista had served, by its count, more than 30 million of the drinks, Delaplane and the owners grew tired of the drink. A friend commented that the problem with Irish coffee is that it ruins three good drinks: coffee, cream, and Whiskey.

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