For richer bourbon flavor, try a higher-proof bourbon such as Wild Turkey 101-proof or Wild Turkey Rare Breed (108 proof). Another variation uses Cuervo Black Medallion. Whatever recipe you use, be sure to use crushed ice, and serve this drink extremely cold, with frost on the glass.
You may want to start with a glass that's spent time chilling in the freezer. Don't forget to serve with a straw for sipping.
8 to 10 mint leaves, plus 1 mint sprig, for garnish
1 teaspoon sugar
2 1/2 ounces bourbon
Twist of lemon peel, for garnish
Confectioners' sugar, for dusting
Chill a (tall) Collins glass in the freezer for 10 minutes.
Combine the mint leaves, sugar, 1 ounce of the bourbon and a splash of sparkling water in the chilled glass. Use a spoon or wooden muddler to gently crush (muddle) the mint into the mixture.
Add a handful of crushed ice and stir vigorously. Add the remaining 1 1/2 ounces of bourbon and a splash of sparkling water. Fill the glass to the brim with ice (tightly packed), then use a bar spoon or knife to agitate the mixture until frost appears on the outside of the glass. Garnish with the mint sprig and lemon twist, and dust the top with confectioners' sugar. Insert a straw and serve immediately.