H.L. Mencken famously called the martini "the only American invention as perfect as the sonnet." The sonnet, as anyone who took freshman English may remember, is a poem with a specific meter, a structure of exactly 14 lines and a strict rhyme scheme. This being the age of free verse, no one writes sonnets anymore. Which is just as well, since almost no one reads poetry anymore.

I've been tasting a lot of silly drinks lately, and I believe we have entered the age of free verse in cocktails. Not long ago, for example, I attended an event that featured 10 of the best bartenders in the Washington area, all trying to out-mix one another. Here are some of the ingredients used in that evening's cocktails: rose hips, yuzu juice, truffle oil, tarragon soda, homemade celery bitters, Sichuan pepper, tonka bean syrup and cherrywood-smoked white pepper meringue. Sometimes I think we're all losing our minds; Mencken would not be amused.

Creativity is to be admired, and it's certainly exciting to fancy oneself a "bar chef." Maybe I'm just a classicist at heart, but a lot of contemporary cocktails bring to mind Robert Frost's assertion that writing free-verse poetry is like playing tennis without a net. Or, in the words of one wise friend, "Dude, every once in a while can I just get something to drink?"

The other day, that same friend asked me to tell him honestly — as a normal human being — what my favorite cocktail is. I thought about a drink with ingredients that don't require a visit to an expensive gourmet shop, an act of Congress to import, or the hiring of a private detective to track down.

That's easy, I said. No contest. The Manhattan.

I am far from alone in that opinion. "The Manhattan, by many accounts, constitutes proof that there's a benevolent force working for us in the universe," A.J. Rathbun writes in his cocktail compendium, "Good Spirits" (Harvard Common Press, 2007).

Duggan McDonnell of Cantina Bebidas in San Francisco was moved to near-poetry in an e-mail: "The Manhattan is the cocktail that every grown man comes of age upon; it is the drink that brings his drinking palate, his social awareness, his willingness to spend and entertain into maturity."

And Todd Thrasher of PX and Restaurant Eve in Alexandria, Virginia says that "in every bar or restaurant in the world, every bartender has a variation of the Manhattan."

With apologies to Mencken, the Manhattan is more complex than the martini and more flavorful. Like a strong poetic structure, the Manhattan's recipe is more of a starting point than a rote list of ingredients. It is both universal and highly personal. The Manhattan encourages modifications, riffs, virtuoso performances.

And it is deceptively simple. In its most basic form, the Manhattan is two parts whiskey, one part vermouth, a few dashes of bitters and a garnish. But that is simply an outline. As any art-school student is told, you have to know the rules before you know how to break them.

• First, will you use bourbon whiskey, or rye? The original 19th-century Manhattan was meant for rye, which is brasher and spicier, but smoother, sweeter bourbon is what I reach for more often. When I use bourbon, I prefer Russell's Reserve or Woodford Reserve. With rye, I generally go for standards such as Wild Turkey 101, Michter's or Old Overholt.

• What vermouth will you use? The basic choice is sweet vermouth, such as Martini & Rossi. But I've tasted excellent versions that use Cynar, Punt e Mes or other Italian amari. Versions such as the Perfect Manhattan call for a little dry vermouth.

• Do not omit the bitters. I cannot stress that enough. The most common cause of a bad Manhattan is a poor bartender who forgets the bitters. Most often I go for a couple of dashes of Angostura bitters, but there are excellent versions that call for orange bitters, Peychaud bitters and others.

• Will you garnish the drink with a maraschino cherry, a lemon twist or both? At the risk of sounding like a bar chef, I suggest making a batch of homemade preserved cherries.

• One last item: A Manhattan is always stirred. That is nonnegotiable.

From here, variations are endless and often named after other New York boroughs or neighborhoods. For instance, I recently enjoyed the Red Hook (2 ounces rye, 1/2 ounce Punte Mes, 1/4 ounce maraschino liqueur) and the Greenpoint (which replaces the Red Hook's maraschino with green Chartreuse).

Three variations that I recommend are the Reverse Manhattan (3 parts sweet vermouth to one part bourbon, plus Angostura bitters), the Manhattan Bianco (equal parts bourbon and bianco, not dry, vermouth), and the Black Manhattan (which adds the Italian amaro Averna to the mix).

"The Manhattan has a special place in my heart," Thrasher says. "When my wife and I started dating, that's what she drank." Though now known for his highbrow libations, Thrasher admits that, back then, he drank mainly Captain Morgan-and-Cokes. "So my wife was more sophisticated than I was."

His version, My Wife's Manhattan, is a bit unorthodox, calling for equal parts sweet vermouth and bourbon. The original recipe also called for a hint of cherry juice, which Thrasher has replaced with cherry bitters. And in an almost heretical move, Thrasher shakes his Manhattan rather than stirring it: "You're never supposed to shake a Manhattan, but that's how she liked it, so that's how I make it."

I guess whoever said stirring was nonnegotiable has a few things to learn about marital bliss. Classicism aside, I approve.

Jason Wilson is editor of The Smart Set. He also edits The Best American Travel Writing series (Houghton Mifflin) and writes the Spirits column for the Washington Post.

Photographs by Lynn Brownlie and Mike Bucher, "Booze" photograph by Lynn Brownlie and Mike Bucher, "Bottle" photograph from istockphoto.com.