The mint julep has been the Kentucky Derby's official drink since 1938, when Churchill Downs started selling it in souvenir glasses for 75¢.
Anatomy of a Classic:
The Mint Julep
by Stephen Stryjewski, of Cochon, New Orleans
At the time of the Kentucky Derby, mint is growing like crazy in Kentucky and it provides just enough background sweetness to compliment the smoky woodiness of bourbon. A julep is actually a good morning mix because it's so refreshing and lets the kick of the bourbon come through. Like a good cup of coffee, a mint julep's got that zing about it.
In a slender Collins glass, muddle five or six mint leaves with one teaspoon superfine sugar and about half an ounce of bourbon until you get a paste. A good julep has to be cold, so pack the glass with crushed ice. Then add three ounces of good Kentucky bourbon like Woodford Reserve. Top off with a mound of crushed ice and a sprig of mint. Using a straw that reaches all the way to the bottom of the glass, give it a quick stir—and you're off.