Before you start mixing this drink, make sure you chill your martini glasses in the freezer for 10 minutes – this will keep your cocktail nice and frosty longer.
Meanwhile, brew a shot of espresso and let it cool to room temperature.
Fill a cocktail shaker with ice cubes and add the vodka, coffee liqueur, chocolate liqueur, cooled espresso, and simple syrup to the shaker.
Shake the mixture vigorously for about 10-15 seconds, so everything will be mixed, chilled, and create a frothy top.
Take one of the martini glasses from the freezer and strain the cocktail into it.
If you want it extra fancy, garnish your Chocolate martini with dark chocolate shavings, cocoa powder dusting, or a few espresso beans.