It seems there are as many versions of cacio e pepe as there are kitchens to produce it. In fact, a search for "cacio e pepe recipe" yields nearly half a million results. 

These results show a lot of people like to use butter for cacio e pepe. And if you've tasted the dish, you'd be forgiven for thinking there was butter in it. Others like to use a combination of pecorino Romano and Parmigiano Reggiano, or pecorino and Grana Padano, or some other mixture. And they'd be forgiven for wanting to temper pecorino's bite, or the heat of so much black pepper. But these ingredients are unnecessary. Incorrect.

Actually, they're perfectly fine, but using them results in a dish that is, simply, not cacio e pepe. Someday I will find the clip from Anthony Bourdain's time in Provence when he bravely serves to his (deeply Provençal) hosts his version of ratatouille, a regional specialty whose proper preparation sparks fervent debate. With withering candor, the matriarch of the family proclaims two true things: "This is good. But this is not ratatouille."

See, what no one talks about is the pure, terrifying, rapturous alchemy of this dish. Actually, this one from Splendid Table whizzes past it just briefly: noting that the sauce can range anywhere from "dry to juicy" is a subtle gesture that results are probably never consistent from cook to cook, and even from day to day in the very same kitchen.

Cacio e pepe is a wild, numinous thing that demands our reverence and cannot be contained to one recipe.

It's an expression. A practice for which one must renounce all ego. For about 20 minutes. So at least it's shorter than a yoga class.

I want to talk about alchemy. The arcane, weird practice of transforming a base metal into gold. An older cousin of chemistry, with far less documentation and, sadly, lacking in equivalency to the torturous high school chemistry class that still gives you occasional night sweats. The allure of alchemy lies in its impossibility: using what looks, to a modern eye, a lot like spells and hocus pocus to turn one humble material into another, much more valuable material. Only thing missing's the eye of newt, right?

Wrong. Any time you cook - anything - you perform an alchemy of sorts. Using what we know about the behaviors and tendencies of plants, animals, roots, and minerals, we routinely take a ragtag, meek assortment of ingredients and turn it into dinner. Or breakfast. A celebration. A communing. Something, anything, to eat. And it's beyond just broth and bread, though on certain days that pairing has its own charms. We know that with the right combination of time and heat, certain things caramelize. We know that with a different combination of time and heat, plus liquid, a cranky and ungainly hunk of meat reveals an adorable secret identity: something friendly and comforting, something that will feed, in a dizzying array of iterations, an entire houseful. For days! In a snowstorm!

We know that every ingredient lends itself to certain techniques and flavors. We know what it wants.

So just as we know now that Brussels sprouts, their secret little hearts misunderstood for ages, wanted all along only to be roasted and crisp, or that short ribs love so dearly to be braised, or that lemon and garlic are the very best of friends, we know that long pasta gets a longing, on occasion, to regress, a thousand past lives ago, to a spare little kitchen somewhere with the three very dearest companions it has known through centuries: salty, sheepy pecorino, black peppercorns just now busted open, and thick, cloudy, hot water.

To make it is to participate in an impossibly long line of home cooks. Who are interested in lunch. Who are interested in dinner. Who are interested in making those last pennies, dollars, lira, Euro, whatever, stretch for one more day. We have dry pasta. We have dried peppercorns. We have a hunk of cheese so freaking salty it will last us into the next decade. 

That's right, if one dish is emblematic of real-life alchemy, it's this one. Cacio e pepe has three ingredients. Four, if you count the water, which you should in this case. And in order to make it with only these ingredients, it also requires intuition, your own expression of technique, and a certain unflappability. 

So you've got your base materials. You've got your hocus pocus. Let's make lunch.

Ordinarily my recipes might include a note or two about technique, or ingredient substitutions, or serving suggestions. Since this dish relies equally on technique and ingredients, I'm treating this section more as mandatory pre-reading/primer/pep talk before we get into the thick of things. 

1. This dish takes practice. I think I tried at least three recipes from well-known food publications before I decided to scrap it all and start from my own gut. The first attempt was shockingly good. Beginner's luck, I thought. The second time, it sucked - I used a different salt in the water and it made a massive difference in flavor, especially once combined with the sharp pecorino. The whole thing tasted like a salt lick. The third time, I was too cavalier with the cheese, adding too much at a time, and overly reliant on tongs instead of the muscle required to repeatedly flip the pasta in the pan, resulting in a serviceable bowl of pasta, but not evenly-coated strands. The fourth time, it was right. All of it. I will mess it up again and I will make it perfectly again, and as arcs of history go I just hope this one bends toward good pasta. But this is a dish to grow on, and I think the journey is totally worth it.
2. In the spirit of practice, I recommend starting with a half pound of pasta and no more. That's enough to serve two hungry people with room on the side for a salad cut with a bright, acidic dressing. You'll want it. 
3. You will notice I call for an unusual vessel here. Normally boiling pasta requires a nice, commodious cauldron of salted water, but here I'm guiding you toward a low, wide pan. This is to significantly improve your water-to-starch ratio in the pasta water, which will yield the ideal consistency to create that luxurious silky jacket coating every strand for cacio e pepe, or really any un-sauced pasta. Yes, that's right - the pasta recipe from this month's issue of Quik & EZ doesn't work because you're using something that's pretty dang close to regular old tap water in a well-meaning but misguided attempt to bind flavorsome bits & bobs together, instead of the revered pasta water of legend, with its superior powers of cling, that so many chefs and grandmothers swear by. It's a new kitchen skill I know you'll find valuable.
4. The mixing all happens in the warm pan where the pasta was cooked. It's tempting to just mix the cheese into the pasta with tongs, and it's necessary here, but only to a degree. That elusive final slick shows up more consistently the more you rely on flipping the pasta in the pan with a classic wrist-jerk. I'm no scientist, but there's something about the force of the flip that allows the long pasta to stretch and meet with as much of the cheese and water as possible, with no friction from you, and with the tiniest breeze as it hops up in the air for a second. I wonder if that doesn't do something to help "set" the coating, help the pasta slip into its jacket. It's a cheffy move, and maybe one you're not super confident with yet, but I promise it's worth the practice.

Ingredients

• 1/2 pound spaghetti
• 2 ounces pecorino Romano cheese, grated finely on a Microplane or box grater
• 1 teaspoon freshly cracked black pepper
• Salt

Method

First, determine the best vessel to cook your pasta. Look for something low and wide with curved sides - you'll be using a lot less water to cook your pasta for this, and you also need something you can flip. My pan of choice is a low, broad frying pan 10 inches in diameter.

Bring about 7 cups of water to a boil. (For me, that's about an inch from the top of the pan.) This will be just enough to cover the pasta - remember, we're looking for concentrated starch. Salt the water generously and stir gently to dissolve.

Lay down the pasta lengthwise across the pan. Using tongs or a wooden spoon, gently drag across the pasta to ensure it's not sticking together. This might feel like you're slowly strumming a guitar with a zillion strings, underwater. Continue circulating the pasta around the pan periodically, then drag the spoon across to strum and separate. Cook on the low end of whatever time is specified on the package. 11 minutes seems to be the sweet spot for me.

While the pasta cooks, set a bowl or, ideally, a large measuring cup in the sink. You'll use this to catch the pasta water.

Taste the pasta for doneness. When it's ready, your teeth should feel some resistance, but you shouldn't have to pick pasta specks out of your molars when you're done chewing. If that's the case, give it another minute and test again.

Drain the pasta by (carefully) bringing the pan over to the sink, and, holding back the pasta with the tongs or wooden spoon, slowly pour the hot pasta water into the measuring cup or bowl. You'll have more water than you need, but how much more depends a lot on conditions. Better safe than sorry. A little water left in the pan is OK, too, as is a strand or two of pasta in the cup. Bring both pan and pasta water back to the stove. Though the burner is off, the area is still warm, as is your pan, which creates the right environment to coax the sauce together.

Dribble a bit of water into the pan, maybe about a tablespoon to start, and move the pan in a quick gentle circle to make sure the water is distributed along the bottom. Sprinkle a very light dusting of cheese evenly over the pasta, about two tablespoons. (It might feel like not enough. It's enough!) Then start to gently flip the pasta in the pan, using your wrist to jerk the pan forward, then back, which will flick the pasta up the side and back down. Once it looks like the cheese has melted evenly and the water has absorbed, add a little more of both - first water on the bottom, and cheese on the top. Flip again. If and when (more likely it'll be when) your wrist/arm gets tired, you can switch to using the tongs to mix gently, but with conviction. Cluster up some pasta in the tongs, then pull it upward to stretch and coat. Do it again with another cluster, then turn the pasta in the pan over a bit with the tongs to mix. Change back to flipping whenever you feel you've got it in you. Keep adding water and cheese until you've got about a handful of cheese left. Add about half of the pepper and toss to combine. Taste and see how you're feeling. Too gloppy? A few splashes of water, one splash at a time, and some vigorous flipping should help. Too bland? Add some cheese and more pepper, and flip several times. I generally add the entire teaspoon of pepper by the end, but that might be too much bite for some. Go according to your tastes.

Serve immediately and top with a small amount of grated pecorino and additional pepper, if desired.

A last note!: cacio e pepe is best eaten right away, as that magical sauce is merely a fleeting suspension of starch and protein. Leftovers will likely be claggy and not at all like their first incarnation. But if you do happen to have more than you can eat, it can be reheated and loosened with olive oil or butter, and maybe given new life with a thinly shaved garlic clove and a splash of cream.

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