2 cups fresh pink grapefruit juice (from 2-3 grapefruits)
1/2 cup St-Germain (elderflower liqueur)
1/4 cup Campari
1 750-ml. bottle chilled sparkling wine
Combine grapefruit juice, St-Germain, and Campari in a large pitcher. Cover and chill until cold, about 2 hours (can be prepared 1 day in advance).
Divide grapefruit mixture among glasses and top off with sparkling wine.
Via Bon Appetit, http://www.bonappetit.com/recipes/2013/05/522-north-pinckney-coc..., the 522 North Pinckney Cocktail is an upgraded mimosa named for bar and spirits director Brian Bartels's former address.