From the authors: We first served this punch for a New Year’s Eve party a few years back and have since made it part of our year-round cocktail rotation. The drink has a unique undertone of citrus and smoke, which comes from orange slices that we caramelize under the broiler. Then we build a classic Champagne cocktail, using simple syrup, bitters and good Champagne, and add a kick of vodka. We love to use Satsuma oranges, a flavorful member of the mandarin family, when they’re in season, but any oranges will do.
On a baking sheet lined with foil, broil the Satsuma orange slices under high heat until slightly charred, about 5 minutes. Let cool. In a large carafe or punch bowl, combine the simple syrup, orange bitters, vodka and charred orange slices with enough ice to fill the carafe or bowl halfway. Stir for 5 seconds. Add the Champagne, stirring once to combine. To serve, pour the punch into chilled coupes and garnish with the orange zest. Serve immediately.