Cinco de Mayo is America’s favorite excuse to overindulge in tequila. But what do you really know about the national spirit of Mexico? I took a trip to the source to learn more.

About a 45-minute drive northwest of Guadalajara, and a couple hours inland from Puerto Vallarta, the diminutive town of Tequila sits in an arid valley at the foot of the dormant volcano of the same name. The landscape of dusky orange and yellow soil is interrupted by patchwork squares of deep blue-green fields of spiky agave plants. This is where tequila gets both its name and its character.

Like other intrinsic denominations (think Champagne, Parmigiano-Reggiano and port as examples), in order to claim the name tequila, the spirit must be made in the state of Jalisco and in certain parts of adjacent states Guanajuato, Michoacán, Nayarit, and Tamaulipas. Moreover -- though there are more than 200 kinds of agave throughout Mexico and beyond -- tequila must also be made specifically with Agave Tequilana Weber Blue. Yet for all those restrictions, tequila is a richly varied spirit. Where and how the agave are grown, and how it is distilled and aged, create profound changes in its flavor.

For example, though all tequila must be made from blue agave, it only needs for 51% of its base to be made of blue agave to qualify. Blends are called mixtos may contain up to 49% of distillates of sugars derived from sugar cane, beets and other sources. So if you want the good stuff, make sure it says “Made with 100% Blue Agave,” and not just “Made with Blue Agave.”

Also: There is no worm in tequila. Any agave liquor made outside the prescribed regions, or made with agave other than the blue agave is called mezcal, and only mezcal is bottled with the worm.

I visited the La Cofradía distillery, on the outskirts of Tequila, which produces the premium Casa Noble tequila. Pepe Hermosillo, president of Casa Noble, met a group of us there to show us how tequila is made from the ground up. Standing among a small patch of blue agave, he introduced us to Quirino, one of the jimadores, or agave harvesters.

With wizened hands, Quirino stood stoically, wielding a wooden dowel with a hefty circular cast iron blade known as a coa. Driving the blade into the base of the plant with a few brief stabs, he pried it free from the earth, then deftly began shearing off the thick, woody blades.

Once cleaned, the heart of the agave is called a piña, resembling as it does a pineapple. The freshly cut piñas give off a grassy, slightly fruity perfume.

When mature at 10 to 12 years, the piñas are full of sugars, particularly fructose. They are slowly cooked in steam ovens for 36 hours to develop the sugars and soften the tough, fibrous flesh. The resulting flesh is dark brown and sweet. The ones we sampled tasted of molasses, smoke, tamarind and orange blossom -- flavors that would translate into the finished product.

The roasted piñas are then shredded and processed through a screw mill with paddles that crush the flesh to extract the sugary fluid. Just as grape juice is fermented to make wine, yeasts convert this fluid to an alcoholic base, called mosto. And then the distillation process begins.

Casa Noble is one of a handful of tequila producers that triple distill. After the first distillation, which gets rid of most of the “heads” and “tails” -- undesirable compounds that boil at higher or lower temperatures than alcohol -- the second and third distillations refine the product further. In the end, the result is a pure, clear tequila, called blanco. (Casa Noble calls their blanco Crystal.) Yet even triple distillation does not strip away the natural flavors of the agave.

Blanco tequilas tend to have bright, clean flavors; Casa Noble’s has high notes of peppermint and citrus, with spicy and floral aromas. These tend to be the go-to tequilas for cocktails. But tequila is also aged in oak barrels. There are three major types of aged tequila: Reposado is aged up to one year; añejo is aged from one to three years; and extra-añejo is aged at least three years. With each successive age, the flavors mature and mellow. You might use a reposado in a cocktail, but most añejos and certainly the extra-añejos are best straight up, like a fine whiskey or cognac.

• Look for 100% blue agave.
• If it has a worm, it’s not tequila.
• Use blanco and maybe reposado in cocktails; savor the añejo and extra-añejo on their own.

Speaking of cocktails, who’s thirsty? Dave Yan, the marketing director at Casa Noble, whipped up one of these numbers for us at lunch. The combination of sweet and spicy play wonderfully with tequila. It’s sure to be a hit at your Cinco de Mayo event.

Note: Tajin is a spice mix widely available at ethnic markets, or is available online. Alternatively, you could use a mix of chile powder, kosher salt and lime zest.

Pour a thin layer of agave nectar onto a small dish, and a layer of the Tajin onto another dish. Dunk each glass’s rim in the nectar, then in the Tajin.

Put cocktail ingredients in blender and blend thoroughly. Serve immediately.

Get more of Cooking Channel's best cocktail and mixed drink recipes.

Sean Timberlake is a professional writer, amateur foodie, avid traveler and all-around bon vivant. He is the founder of Punk Domestics, a content and community site for DIY food enthusiasts, and has penned the blog Hedonia since 2006. He lives in San Francisco with his husband, DPaul Brown, and their hyperactive terrier, Reese.