Start by brewing a fresh shot of espresso using an espresso machine or a Moka pot. If you don't have an espresso machine, you can also use strong brewed coffee or instant espresso.
Add ice to a cocktail shaker and pour in the vodka, coffee liqueur, fresh espresso, and simple syrup.
Shake the cocktail shaker vigorously for about 10-15 seconds, until the liquid is well chilled.
Strain the cocktail into a chilled martini glass.
If desired, garnish the cocktail with a few coffee beans on top.
And that's it! Your delicious Espresso Martini is now ready to be enjoyed.