- 3½ pounds chopped seedless watermelon (about 12 cups) cut into 2 inch cubes
- 1 cup tequila
- 1 cup freshly squeezed lime juice (6–8 limes) plus lime slices for garnish
- 4 cups ice
- ¾ cup sugar
- Stir together sugar and ¾ cup water in a medium saucepan. Bring to a boil over medium-high heat, stirring until sugar is dissolved. Let cool completely. Refrigerate until ready to use, up to one week.
- Working in batches, purée watermelon in a blender until smooth. Past purée in batches through a fine sieve set over a large bowl, discarding solids as you work. Refrigerate juice until ready to use, up to 1 day.
- Stir together tequila, lime and watermelon juices with simple syrup in a large pitcher. Stir in ice and lime slices.