Rim a martini glass with crushed sugar cookies using a bit of vanilla syrup.
Fill a cocktail shaker with ice and add vodka, coffee liqueur, espresso, Irish cream, and vanilla syrup.
Shake vigorously for about 15 seconds until well chilled.
Strain into the prepared martini glass.
Top with whipped cream and a dusting of cinnamon or cocoa powder, if desired.
Serve immediately and enjoy!