6 peaches, (about 1 pound, 8 ounces), halved and pitted 1/4 cup superfine sugar, plus more for garnish 1/4 cup water 1 bottle Prosecco (750 ml or 3 1/3 cups), chilled
With a box grater grate peaches into a pitcher. Add the sugar and water to the peaches and place pitcher in refrigerator until chilled and sugar has dissolved, or until needed.
When ready to serve pour the superfine sugar on a plate and invert a chilled Champagne glass in the sugar to coat rim. Pour about a 1/8th of the peach mixture into the prepared glass and top off with Prosecco. Stir gently and serve.