1 oz of Jack Daniel's Tennessee whiskey
1 oz of Lemon Juice
1/4 oz of sugar syrup
1/4 oz of Blue Curacao (or orange liqueur)
Put some crushed ice in a small glass. Shake the Jack Daniel's, the lemon juice and the sugar syrup, mixing well. Pour the resulting milky fluid over the crushed ice. To complete the drink, pour all the blue Curacao over the ice (as a big dash). The milky fluid will now fade into blue.