Christmas Champagne Cocktail

Makes about 2 quarts
1 1/2 cups water
1 1/2 cups sugar
1 (12-ounce) bag fresh or frozen cranberries
2 (1-ounce) packages fresh mint
2 (750-milliliter) bottles Champagne, chilled
Garnish: cranberries, fresh mint

1. In a medium saucepan, combine water and sugar over medium-high heat; stir until sugar dissolves. Add cranberries, and bring to a simmer. Reduce heat to medium, and cook for 5 minutes, stirring frequently. Remove from heat, and add mint. Cover, and steep for 15 minutes.
2. Press cranberry mixture through a fine-mesh strainer, discarding solids. Let cool completely. To serve, pour cranberry syrup and Champagne into a large pitcher, stirring gently to combine. Garnish with cranberries and fresh mint, if desired.