The key to a good margarita is real tequila, about which plenty of amateurs don't know the first thing. Hint: If you think tequila looks like warm piss after a tennis match, just give up now. You're probably one of those folks who believe the best pizza is made by Domino's, in which case you shouldn't be drinking anyway. But if you understand that real tequila has to be made from only 100 percent blue agave cactus, then you know what it's supposed to taste like. Not only does Canyon use blue agave, but Canyon's patented recipe calls for a second variety of cactus, the prickly pear, in lieu of lime juice. Used to being questioned about their regionally recognized margarita, the waitress is quick to point out the purple-liquid-filled vat on the bar where Sauza Hornitos tequila infuses the peeled prickly pear fruit for 48 hours. The finished product, to which sour mix and triple sec have been added, is served frozen or on the rocks (the house's recommendation) in sleek martini glasses. We prefer it frozen, so that every icy, biting sip burns a trail down our throats. If you're looking for the typical margarita experience of washing down chips and salsa with gulps from quart-size glasses, this place is not for you. But if you're looking for a memorable margarita and don't mind spending around six bucks for one, saddle up and head down to Canyon.