Fill your martini glass with ice water before you start, then empty it before pouring.
Brew a fresh shot of espresso and let it cool slightly while you prepare the other ingredients.
In a cocktail shaker, add the vodka, coffee liqueur, cooled espresso, and simple syrup.
Fill the shaker with ice cubes to the top.
Secure the lid on the shaker and shake vigorously for about 15–20 seconds.
Strain the mixture into a chilled martini glass. You can use a fine strainer to ensure a smooth texture.
If desired, garnish with three coffee beans for a classic touch.
Enjoy your Espresso Martini immediately!