Chill a martini glass
Add chocolate syrup to a plate and rim the glass if desired
Fill a cocktail shaker with ice
Pour in 2 oz vodka
Pour in 1 oz chocolate liqueur
Pour in 1 oz Irish cream or cream liqueur
Add 1 oz cream or half-and-half
Shake well until chilled
Strain into the prepared glass
Garnish with chocolate shavings or a cocoa-dusted rim if desired