- 1/2 cup granulated sugar
- 3/4 cup chilled club soda
- 1 1/2 cups gin
- 1 1/2 cups fresh grapefruit juice, plus 3 thinly sliced grapefruit wheels,
- 3/4 cup fresh lemon juice
- 3/4 cup sweet vermouth
- 2 1/4 cups chilled Champagne or sparkling wine
In a large pitcher, stir the sugar with the club soda until dissolved. Stir in the gin, grapefruit and lemon juices and sweet vermouth and refrigerate until chilled, about 1 hour.
Transfer the punch to a large bowl. Gently stir in the Champagne and float the grapefruit wheels on top. Serve in punch glasses over ice.