In honor of the day, or should I say honour, I'll not only be wearin' the green, but drinkin' the Irish as well. Mug in hand, I went in search of the origins of the stuff.
According to about.com,
The Port of Foynes, which is located in County Limerick, was a major hub for for air traffic between the United States and Europe during the 30's and 40's. Travel was by Flying Boats. One flight that took off in 1943, encountered some really bad weather and turned back. The weather was equally as nasty upon their return and the passengers headed towards the terminal restaurant. Realizing how miserable these passengers were, Chef Joe Sheridan grabbed a bottle of Irish and prepared the comforting drinks. Legend has it that one of the passengers asked, "is this Brazilian coffee?", to which Sheridan answered, "No, that's Irish Coffee."
The Buena Vista in San Francisco helped to bring this renowned drink to the States in 1952. Owner, Jack Koeppler, made his way to Ireland to learn the secrets of Irish Coffee from the horses mouth; Joe Sheridan. Thank you Jack!
The Buena Vista website tells the story about Jack's search for the perfect whiskey and the perfect cream. You can read the rest of the story here: https://www.thebuenavista.com/irishcoffee.html
Discover Ireland gives us the recipe and proper instructions:
1 Measure (3 cl) of Irish Whiskey
1 teaspoon of raw sugar
1 heaped desertspoon of whipped cream
Hot strong coffee to fill the glass
Pre-warm a stemmed glass. Add the whiskey. Add the sugar and stir in the coffee.
Float the whipped cream on top. Drink the coffee through the cream (ie do not stir after adding the cream).
And if you really want to do it up right, here's a recipe for Irish Coffee Cake: https://www.recipesource.com/baked-goods/desserts/cakes/01/rec0100.html
Go n-eírí an bóthar leat.
May the road rise with you.