As the weather warms and the Kentucky Derby and Gold Cup races approach, there's no better time for a mint julep. The icy cocktail--a sort of snow cone for grownups--has been keeping Derby fans cool since the Churchill Downs racetrack opened in 1875.

One of the earliest records of the mint julep is an 1803 British travelogue, in which the writer mentions drinking them on a Northern Virginia plantation.

In Washington, the official line is that Kentucky statesman Henry Clay introduced the julep in the early 1800s at the hotel where the Willard InterContinental now stands. Bartender Jim Hewes makes at least two dozen a day in the summer at the Willard's Round Robin Bar. He says juleps "evoke an era of hospitality and geniality, when you were offering the best of what you had: whiskey, ice--which was hard to come by--mint, and time. They're labor-intensive."

Ladies and gentlemen, start frosting your julep cups.

Henry Clay's Kentucky-Style Mint Julep

(As interpreted by Round Robin bartender Jim Hewes)

2 ounces Maker's Mark bourbon (or another premium Kentucky bourbon)

2 ounces San Pellegrino sparkling water

8-10 fresh mint leaves, plus a sprig of mint for garnish (Hewes uses red-stem mint)

2 cups crushed ice (dry, not slushy)

1 teaspoon granulated sugar plus a bit more to taste

1 thin strip lemon peel

1 julep cup (crystal or silver), frosted in the freezer

1 straw

Add one teaspoon of sugar, the mint leaves, one ounce bourbon, and one ounce sparkling water to the julep cup. Using the heel of a butter knife, muddle for about a minute until it forms a tea. Add a half cup of crushed ice and muddle some more. Add the rest of the ice, keeping it tightly packed. Pour in the rest of the bourbon and sparkling water. Garnish with a sprig of mint and top with the lemon peel and a dusting of sugar. Wedge the straw just behind the mint sprig so when you lean in for a sip, you get a peppery whiff.