- 6 fresh shiso (or mint) leaves, plus 8 additional sprigs for garnish
- 12 3/4 cups (2 3/4 quarts) cubed seedless watermelon, pureed and strained (makes 1 1/2 quarts juice)
- 1 2/3 cups white rum (or to taste)
- Crush shiso in the bottom of a large pitcher, using a long wooden spoon. Add watermelon juice and rum; stir. Serve over ice; garnish with shiso sprigs.