With only 4 ingredients (counting ice) it doesn't seem like you could mess it up, but a classic mint julep cocktail "is one cocktail that's been bastardized more than others," says Christopher Evans, bartender at Bourbon on Rye in Lexington, KY.
The mint julep cocktail as we know it in America today has its roots in Kentucky where bourbon is king. Once upon a time mint juelps were made with brandy, gin, or other spirits based on preference. Today classic mint julep ingredients are pretty well agreed upon: Mint (spearmint, not peppermint), crushed ice, bourbon, and sugar. Of course, exactly how to make a mint julep will always vary a bit from bartender to bartender, but here's how I learned to make a mint julep from one Kentucky bartender.
Sure, you can serve a mint julep in other cocktail glasses, no harm done, but traditionally a silver (specifically Lexington silver) or pewter glass is used for this cocktail recipe. Once filled with crushed ice and the cocktail fixings, you get an enviable frosty glass that stays cold. Hold the glass at the top or bottom to keep the frosty exterior.
No one could tell me exactly why we use crushed ice in mint juleps, but everyone agreed the crushed ice part is what makes a mint julep a mint julep. Best guesses include that the dilution rate is agreeable and it helps keep the julep cup cold and frosty.
Crushed ice tricks: If you don't have crushed ice at the ready there are a few ways to make your own crushed ice at home:
Remove as many stems as possible and muddle mint leaves in the glass you'll be serving your mint julep in. No need to pulverize the mint, just muddle it enough to get the oils on the inside of the glass for flavor and aroma. Dispose of the muddled leaves (this helps with keeping green out of your teeth, too).
Really pack the crushed ice into your mint-seasoned julep cup. I'd wager most every mint julep you've ever seen had mounded ice coming out of the top.
Pour 2 ounces of bourbon slowly over the ice, trying to melt some of the ice before the bourbon reaches the bottom of the cup. A Kentucky bourbon, such as Maker's Mark, is obviously the expected choice here, but we'll keep it a secret if you use another favorite bourbon.
Pour ½ to ¾ ounce simple syrup into the glass, depending on the level of sweetness you desire. You could also use the sugar and water technique since that's all simple syrup is, but each place I got a mint julep at in Kentucky used simple syrup. You can buy simple syrup or make your own.
How to make simple syrup: In small saucepan, combine and simmer 1 cup water and 1 cup sugar. Cook and stir over medium heat until sugar is dissolved, about 4 minutes. Set saucepan in bowl of ice water until syrup is cool. Or chill until ready to use.
My favorite mint julep tip from Evans! Obviously you always serve a mint julep with a garnish of fresh mint, but before adding the mint, give it a smack against the outside of your wrist or clap it between your hands. This releases some of the oils and gives off more minty aroma. That way when you take a sip the mint scent hits your nose, big and bold.
It's up for debate if you need a straw for this drink, but most agree if you're using a straw it should be paper and short so your nose gets right on into the drink. One of the mint juleps I tasted used a silver spoon/straw, which was a longer straw length, but made for one seemingly fancy drink. The spoon part allows you to keep the cocktail well mixed, and the straw part keeps the drink cold all the way to your lips, plus it's earth-friendly. Cheers!