Add cocktail ingredients to a shaker filled with ice. Shake until chilled-- about 30 seconds.
Drizzle chocolate syrup on the inside of a chilled cocktail glass (optional). Strain the cocktail into the glass. Garnish with chocolate shavings, if desired. Serve immediately.
Notes
For a stronger cocktail add 1 ounce of vodka and cut the cream to 1/2 ounce.To prepare grasshoppers for a crowd I would recommend using a cup of each ingredient. Then shake and strain into glasses immediately before serving so that they drinks are well-chilled.