Instructions
Make the syrup: In a saucepan, combine Fever Tree Sparkling Grapefruit and sweetener over low heat. Stir until dissolved for a few minutes. Remove from heat and allow to cool. Transfer to a bottle or glass measuring cup and chill.
When ready to serve, combine everything in a large punch bowl or pitcher.
Ladle into coupes or Champagne flutes.
Garnish with a sprig of rosemary.
