1 bottle (750 ml) Moet Chandon Holiday Edition Blanc de Noirs, chilled
Grapefruit slices, cinnamon sticks and fresh mint (optional, for garnish)
To make the punch base (prepare it at least 4 hours before serving, the day before is best): Combine grapefruit zest, lemon zest and sugar in a bowl. Using a muddler or wooden spoon, thoroughly massage zest to express the oils and mix with the sugar. Let rest for at least 2 hours.
Once sugar is saturated in citrus oil, add the grapefruit juice, lemon juice, Chambord and bitters. Mix completely until all sugar is dissolved. Strain out the zest solids. Store in the refrigerator.
To serve: Add the punch base to a large punch bowl or pitcher. Stir in the chilled sparkling wine. Garnish with grapefruit slices, a few cinnamon sticks and mint leaves, if desired.