1 1/2 ounces silver tequila
1 ounce orange liqueur (Cointreau, Grand Marnier or Triple Sec)
3/4 ounce freshly-squeezed lime juice
optional sweetener: agave nectar or simple syrup, to taste
lime wedge and coarse salt for rimming the glass
Salt the rim (optional). Run a lime wedge (the juicy part) around the top rim of your serving glass. Fill a shallow bowl or plate with salt, then dip the rim until it is covered with your desired amount of salt. Set aside.
Make the margarita mix. Add tequila, orange liqueur, lime juice and a few ice cubes to a cocktail shaker. Cover and shake vigorously for about 10 seconds. Give the mix a taste and stir in a teaspoon or two of sweetener if desired.
Serve. Fill the prepared serving glass with ice. Strain in the margarita mix, garnish with a lime slice, serve and enjoy.