To a cocktail shaker, add all the ingredients, except ice and garnish. Dry shake for about 30 seconds.
Then, add ice to the cocktail shaker, and shake for another 15-30 seconds. Pour into martini glasses and serve immediately.
Notes
Espresso Alternative: You can sub a shot of espresso for instant coffee or strong brewed coffee. if you prefer to use Instant coffee, here's a good one.
Serve Immediately, to avoid the ice diluting the drink. If there is extra left in the cocktail shaker, remove the ice, or pour into an empty glass.