Pineapple Agua Fresca Party Punch
In a blender, combine half the pineapple, sugar, rum and lime juice and puree until smooth. Transfer to a 3 quart pitcher and add the water. Repeat with the remaining pineapple, remaining sugar, rum and lime juice and stir well to combine, making sure that the sugar is completely dissolved. Refrigerate until thoroughly chilled. Serve in tall glasses filled with ice and garnished with cilantro leaves.