Chill the Glass:

Start by chilling your martini glass. You can do this by filling it with ice water and setting it aside while you prepare the drink.

Mix the Drink:

In a shaker, add ice cubes to cool the liquids quickly.

Pour the vodka, triple sec, blueberry juice, and lime juice over the ice.

Secure the lid on the shaker and shake vigorously for about 15-20 seconds. The shaking not only mixes the cocktail but also chills it further and adds a bit of dilution, which is essential for the perfect cosmopolitan.

Prepare the Glass:

Empty the ice water from the martini glass and strain the mixture into the glass. Using a fine mesh strainer can help ensure that no unwanted ice chips end up in your cocktail.

Garnish and Serve:

Garnish with fresh blueberries. You can either drop a few berries into the drink or skewer them on a cocktail stick for a more decorative touch.

Optionally, you can add a twist of lime peel for an aromatic garnish.