Here it is. Just a really good, basic margarita. Sure, you can use cheap tequila and triple sec but, once in a while, you just have to go for broke.
2 oz 100% agave blanco tequila
1 oz Cointreau (not triple sec)
3/4 oz FRESH lime juice
Sweet and sour mix (optional)
Shake all ingredients with ice
Pour with ice into a salt-rimmed glass
Garnish with a slice of lime