Chill the martini glasses by placing them in the freezer for at least 10 minutes before preparing the drink.

In a cocktail shaker, add ice cubes to fill it halfway.

Pour the vodka, chocolate liqueur, heavy cream, and chocolate syrup into the shaker.

Shake vigorously for about 15-20 seconds until the mixture is well-chilled.

Remove the chilled martini glasses from the freezer and drizzle chocolate syrup around the inside rim for decoration.

Strain the mixture into the prepared martini glasses.

Garnish with chocolate shavings on top and serve immediately.