1 jigger (1.5 oz) tequila
2 Tablespoons (1 oz) lime juice - bottled more convenient, fresh tastes a lot better
1/4 cup (4 Tablespoons) water
1/4 teaspoon orange extract
1 Tablespoon's worth artificial sweetener (I like to use liquid, carb-free types)
Ice - small handful
Margarita salt or kosher salt
Wet the rim of the glass and dip into a small plate of salt.
Combine all ingredients. You can either serve it over ice (in Mexico I've usually been served it this way, but I can't say I've had extensive experience), or strained into the glass, or blended in a blender.
2 grams of carbohydrate using bottled lime juice, 2.5 for fresh