Frozen or On the Rocks: To make this margarita "on the rocks," prepare a highball glass with salt the same way. Fill with ice. Stir together the three ingredients and pour over ice.
If you want a frozen margarita, stir up the mixture and place covered in freezer for two hours. At the same time, prepare martini glass as above and place in freezer. When the time has passed, pour into glass and serve. This will not be like a Slurpee, but it is a true frozen margarita.
The Classic Margarita: To make a classic margarita, follow the same directions.