6 cups pink grapefruit juice, chilled
2 cups elderflower liqueur (such as St-Germain)
2 750-milliliter bottles Zonin Prosecco, chilled
1 pink grapefruit, thinly sliced
1/2 cup fresh mint leaves
In a large punch bowl, combine the grapefruit juice and elderflower liqueur; chill for up to 12 hours. Just before serving, add Zonin Prosecco, grapefruit slices, and mint.