40 blackberries, plus extra berries for garnish
7 ½ ounces superfine sugar
7 ½ ounces lemon juice, from about 3 large lemons
7 ½ ounces VS cognac
20 ounces Brut sparkling wine or Champagne
Lemon wheels, for garnish
In a blender, combine the 40 blackberries, sugar and lemon juice and purée. Strain, removing any seeds and particles.
Place the purée with the cognac and ice in a large cocktail shaker and shake to chill for about 30 seconds.
Pour the mixture into a punch bowl and add ice. Top with sparkling wine, use a ladle to lightly stir, and garnish with plenty of blackberries and lemon wheels. Serve immediately.