After Guinness, the Irish coffee is quite possibly Ireland's most famous drink. This hot cocktail is a mixture of coffee, whiskey, sugar, and cream. It's famous thanks to the Buena Vista Cafe, a San Francisco establishment that perfected the recipe in 1952 and has since served countless Irish coffees — including the world's largest one ever. I headed to the cafe to learn its signature technique for making Irish coffee. Here, bartender Paul Nolan, who's been at the cafe for 32 years and estimates he's poured over 3-4 million Irish coffees, teaches us how it's done.