> 6 limes, divided
> 3 tbsp sugar
> 1 tsp kosher or margarita salt (optional)
> 1/4 cup triple Sec
> 2/3 cup blanco (or silver) tequila
> 3 cups ice, plus more if needed
Squeeze 4 limes into a medium bowl, aiming for ⅔ cup juice. To bowl, add the sugar and stir until mostly dissolved.
If desired, to a small plate, add the salt and spread in an even layer. Cut 1 lime into wedges. Run 1 lime wedge around the rims of margarita or rocks glasses. Dip the rims into the salt to adhere. Cut remaining lime into wheels for garnishing.
To a blender, add lime juice mixture, triple sec, tequila, and ice. Purée 1–2 min., until a slushy consistency. Pour immediately into prepared glasses. Garnish glasses with lime wheels.