The Espresso Martini...

1 oz cold espresso
1 1/2 oz Absolut® vodka
1 1/2 oz Kahlua® coffee liqueur
1 oz white creme de cacao

Pour ingredients into shaker filled with ice, shake vigorously, and strain into chilled martini glass. It should be somewhat frothy. You can garnish this in a number of ways. I use a mixture of sugar and cocoa powder on the rim and sometimes a froth of steamed milk foam.