1/2 watermelon, cubed
3/4 cup tequila
1/4 cup lime juice
1/4 cup white sugar
Place watermelon in a blender; blend until smooth. Pour through a fine mesh strainer to remove seeds and pulp.
Pour watermelon juice into ice cube tray; place in freezer until frozen, about 3 hours.
Place 4 cups of frozen watermelon cubes, tequila, lime juice, and sugar into a blender; pulse until smooth.