Big Batch Option: To serve 8, you will need 8 lemons (seeds removed and quartered), 2 1/2 cups mint leaves, 1/3 cup granulated sugar, 2 cups white rum, 4 cups soda water. Muddle together lemon quarters, mint leaves, and sugar together in the bottom of a pitcher. Add rum and fill with ice. Stir to combine. Top with soda water and serve.