Mix all the ingredients except the whipped cream and chocolate powder in a blender for 15 to 20 seconds, or until smooth. Pour into a tall glass and top with whipped cream and chocolate powder, if desired.
Variations: For a Vanilla-Coffee Crush, omit the chocolate syrup and substitute 1/4 teaspoon vanilla extract. Proceed as directed above.
For a Creamy Coffee Crush, simply omit the chocolate syrup.