Paul Nolan, veteran bartender at the Buena Vista Café,  shares the best method to perfecting the Irish classic, an Irish coffee.

San Francisco watering hole, the Buena Vista Café knows a good Irish coffee - and so too does its veteran bartender Paul Nolan.

While the bar and eatery opened its doors in 1916, it's largely thanks to Nolan that it has received national acclaim as the home of the Irish coffee. The Irish American bartender has been making Irish coffees, most days, for over 40 years.

He takes the bar owner's word for it that he has made between four to five million of them over the decades.

According to Nolan, Irish coffee first came to America back in 1952.

"The original recipe came from Ireland, by the inventor, Joe Sheridan, and he gave the recipe to the beat writer of the Chronicle, Stan Delaplane," Nolan said.

Read more: The real story about Irish coffee and how it was invented

Irish Coffee, at a San Francisco institution

For more than 40 years, bartender Paul Nolan has been mixing the drink that made the Buena Vista Café famous

— CBS Sunday Morning  (@CBSSunday) November 18, 2018

That recipe that Nolan prefers is  two sugars, hot coffee, and an ounce and a third of Irish whiskey.

The pièce de résistance? A layer of decadently delicious heavy cream on top.

Read more: The absolutely perfect recipe for Irish coffee

A recent CBS report revealed that a "truckload of Irish whiskey" is delivered to the bar every week. It's added that the Buena Vista goes through a staggering one hundred bottles of uisce beatha EVERY day!

The reporter also maintained that this one San Francisco institution is the single biggest consumer of Irish whiskey in the world.

Irish coffee at the iconic @theBuenaVista! Entertaining skills of Paul Nolan! So atmospheric! #hastobedone #slainte

— ellen dunne (@excusemel) December 29, 2015

Bob Friedman, who bought the iconic bar back in 2001, notes that they sell about 250,000 Irish Coffees per year. At first, he said he didn't even like the famed tipple - but some years later, he's grown to be quite fond of it.

How do you make your Irish Coffee just right? Let us know in the comments below.

Read more: Ice pops for adults - the Irish coffee version