Place the currants in the freezer for about 30 minutes prior to making the cocktail. (They will act as mini ice cubes and will keep the cocktail colder longer!)
Add the black currant syrup to the bottom of a champagne flute. Top with sparkling apple cider, or Champagne, if using. Drop a couple of currants into the glass and garnish with a small frozen bunch, if desired.
Cook's Note: For the ultimate in crowd control, prepare a pitcher of Ruby Royales; just make sure to add the chilled sparkling cider just before serving so everyone will enjoy the bubbly. A pitcher will allow you to mingle with your guests without playing mixologist.