Jean-Georges Vongerichten served this effervescent sour-cherry cocktail for his guests at the pig roast. He added yuzu juice (from the bumpy-skinned Japanese citrus fruit) for a citrus kick; a mix of tangerine and lime juices nearly matches yuzu's flavor. More Champagne Cocktails
Puree the cherries in a food processor. Pass the puree through a fine strainer set over a small saucepan, pressing on the solids; you should have 1/2 cup of juice. Stir in the sugar and bring to a simmer over moderate heat, stirring to dissolve the sugar. Transfer to a small bowl and refrigerate until chilled, about 15 minutes.
In a large pitcher, combine the sweetened cherry juice with the yuzu juice. Slowly pour in the Champagne. Serve the Bellinis over ice.
The sweetened cherry–and–yuzu juice can be refrigerated for up to 2 days.