For a nonalcoholic version, skip the tequila and add a little water to help blend the mixture.
1 seedless watermelon (about 6 lbs.)
3/4 cup lemon juice
2 cups silver (also called blanco) tequila
How to Make It
Cut melon into chunks and discard rind. Purée chunks in batches in a food processor. Pour mixture through a strainer into a bowl. Pour 4 cups into another bowl; whisk in lemon juice. Save any remaining watermelon juice for another use. Pour juice mixture into 4 ice cube trays* and freeze until firm, at least 3 hours or overnight.
Make drinks: Whirl half the watermelon cubes in a food processor until broken up, then add 1 cup tequila and whirl until blended. Pour into a pitcher and repeat with remaining ingredients.