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If you've spent any amount of time in coastal New England, you've probably noticed how generously awards are bestowed upon clam chowders. Now I've never met the folks who run these award factories, but I take issue with any organization that passes out praise like flyers.
Having spent my entire life traveling through New England, I've grown accustomed to the fact that nine out of ten "award-winning!" or "#1 voted!" clam chowders are going to arrive at the table either thick as paste, bereft of clams, or packed with clams so rubbery they make your jaws bounce, and unfortunately, most home recipes don't turn up results that are much better. And if finding great chowder in its birthplace is difficult, you can imagine what it's like outside of New England.
When done right, clam chowder should be rich and filling, but not sludgy or stew-like. Its texture should be creamy without feeling leaden, like you're sipping on gravy. Tender chunks of potato should barely hold their shape, dissolving on your tongue, their soft texture contrasting with tender bites of salty pork and briny clam; god help the clam shack that dare serves rubbery clams in their chowder!
The flavor of a clam chowder should be delicate and mild, the sweetness of the pork complementing the faint bitterness of the clams, accented by bits of celery and onion that have all but dissolved into the broth, fading completely into the background. A good grind of black pepper and a bay leaf or two are the only other seasonings you need, unless you count the requisite oyster crackers as seasoning. I know some Yankees who do.
Chowders have a long, complex, and relatively apocryphal history that can be traced back to the fish and seafood stews eaten in coastal England and France. Like many old dishes, the name of the food stems from the word for its cooking vessel, a large cooking pot or "cauldron," known in French as a chaudiere. Or perhaps it comes from the old English term for a fishmonger jowter, which had been in use in Cornwall since at least the 16th century.
Whatever the etymology, its history can be traced across the Atlantic to the fishing towns of New England—Boston, Mystic, Nantucket, New Bedford—where the European dish was adapted to work with sea journey-friendly staples like onions, potatoes, and salt pork or beef, along with local ingredients like cod, oysters, and clams.
About a decade ago, I had a job as a cook at B&G Oysters in Boston's South End, a fancy-pants seafood shack run by Barbara Lynch. It was there that I first started taking a serious interest in chowder-making, there that I realized that chowder is not just the sludgy stuff I'd been raised to believe it was. We made our chowder in the manner of a fancy restaurant—cooking and seasoning each element individually, combining, pureeing, straining, adding, mixing, until our broth was intensely flavored and light, our clams were perfectly tender, and every vegetable cooked just so.
It was delicious, but It's decidedly not the way a traditional chowder is made; a poor man's food meant to take few ingredients and even less effort. I remember thumbing through a copy of 50 Chowders, by Jasper White, in which he unearths New England's oldest-known printed recipe for chowder, from the September 23rd, 1751 edition of the Boston Evening Post
Because in Chouder there can be not turning; Then lay some Pork in slices very thing, Thus you in Chouder always must begin. Next lay some Fish cut crossways very nice Then season well with Pepper, Salt, and Spice; Parsley, Sweet-Marjoram, Savory, and Thyme, Then Biscuit next which must be soak'd some Time. Thus your Foundation laid, you will be able To raise a Chouder, high as Tower of Babel; For by repeating o'er the Same again, You may make a Chouder for a thousand men. Last a Bottle of Claret, with Water eno; to smother 'em, You'll have a Mess which some call Omnium gather 'em.
Aside from the interesting technique of layering ingredients in a post to stew them and the very Victorian use of spices, the recipe essentially reads "put things in a pot and cook them." One thing you'll immediately notice is that dairy is conspicuously absent from the recipe. Instead, the chowder got its thickness and richness from soaked biscuits. (Note that in this usage, biscuits most likely refer to tough, cracker-like hardtack, not the fluffy leavened biscuits of the American south).
Slowly, as dairy became cheaper and more readily available in the region, it began making larger and larger appearances in chowder, at first simply being used to moisten the biscuit, before eventually completely replacing it as the primary ingredient outside of clams, pork, and aromatics. These days, the biscuits live on in the form of oyster crackers, which as any true chowder-head can tell you, should be added liberally to your bowl and allowed to soften slightly before consuming.
So which is the best way to cook chowder? Can the dump-and-simmer method be improved upon by some modern technique, or is there something to the classic that gets lost when fiddled with too much?
I decided to break it down element by element and really figure out what it is that makes clam chowder tick.
Building a Base
Most basic recipes for clam chowder call for rendering down some form of salted pork (bacon or salt pork usually), sweating onions and celery in the rendered fat, a touch of flour, followed by milk, potatoes, chopped, and occasionally bottled clam juice. It all gets simmered together with a bay leaf or two until the potatoes are cooked and the broth is thickened. It gets finished with a bit of cream, or perhaps some half and half.
Right off the bat, there are some issues I have with this process—flour-based roux can be pasty, and cooking the clams as long as the potatoes is a surefire path to rubbery clams. These issues would all need to be addressed. But first things first.
There are a few salted pork options at the supermarket:
- Sliced Bacon is the most widely available, and what most folks buy for breakfast. It works in a chowder, but I find the smoky flavor of bacon can be a little overwhelming for the delicate clams. Thin slices also achieve an unpleasant texture as they simmer in the broth. A better option is...-
- Slab Bacon, cut into 1/2- by 1/4- by 1/4-inch lardons (that's fancy French for "chunks") is a much better option. I like the meaty chunks you end up with in the broth. They match the texture of the clams, making the whole dish more cohesive. But again, its smokiness can be distracting, which leads us to...
- Salt Pork, which is simply salted and cured un-smoked pork fat and meat. It can be made from three different parts of the pig—belly, side, and back. The further up the back you go, the fattier the salt pork gets. I find the fat back to be a little too fatty, turning soft and greasy in the chowder. Better is to look for salt pork with an equal mix of fat and lean.
- Countnecks, the smallest size legally harvested. They are not too common.
- Littlenecks, the next size up, and what you are likely to encounter at a raw bar, or on top of a Connecticut pizza.
- Topnecks, one size bigger than a littleneck, but not as large as a cherrystone. The term is very rarely used—you're more likely to see them lumped in with either the littlenecks or the cherrystones at the fish market or in a restaurant.
- Cherrystones are quite large—usually around 4 to 7 to a pound—and are used primarily for stuffing and baking. Finally...
- Quahogs (pronounced KO-HOG) are the largest, sometimes weighing as much as half a pound or more. Round where I grew up, they're known as "chowder clams," and it's for good reason—their large size makes them very easy to process for chowder, and not great for much else.
With any form of pork, the key is to go low and slow so that the fat renders out completely without letting the pork burn. This gives you a great base in which to sweat your vegetables.
Of course, you can also go completely pork-less—there is plenty of precedent for that.
Onions, celery, and bay leaf are the traditional flavorings here, and I found no reason to stray from them. I tried a few versions with things like carrots, thyme, leeks, and garlic, but in all cases found them to be distracting, taking away from the inherent chowderiness of the broth. It simply didn't taste like childhood to me with the alternatives.
Here we begin to see a bit of micro-regional variation. Just as Eastern North Carolina Barbecue differs from Western North Carolina Barbecue, so does New England clam chowder made in Cape Cod differ from that made in, say, Mystic, Connecticut. The variation largely comes down to the size of the clam used.
Clams are slow-growing bivalves, and their size can vary tremendously depending on the age at which they are harvested. Under the best conditions, a clam can grow up to quahog size in 3 to 4 years.
At a good market, you might run into the following types of live clams:
On the Cape, most chowders are made exclusively from quahogs—they're inexpensive, and very meaty. Smaller littlenecks and cherrystones are better reserved for more expensive uses like raw bars and baking.
But does that mean what we ought to be stuck using them at home?
I cooked batches of chowder side-by-side, using variously sized clams and found that in the end, cherrystones and littlenecks were actually superior to quahogs, offering a more tender texture.
Fresh Clam Alternatives
Ok, I get it. Some people just can't get fresh clams where they live. Is it the end of the world? Not really. Many restaurants—reputable ones who make great chowder, at that—use canned or frozen chopped clams to great effect. Clam juice can also be an effective way of adding in some clam flavor—even when the fresh guys are available. I prefer frozen chopped clams to minced canned clams.
Whatever clams you choose to use, there's still the question of the best way to cook them.
For fresh clams steaming is the method of choice. By adding a bit of liquid (plain water or clam juice work fine) to the pot after sweating my aromatics and adding the clams, I could get the suckers to steam open in a matter of minutes. I pull them out of the pot as their shells pop open, draining their liquid into the pot, then removing the flesh with a spoon before roughly chopping it.
In no time, you should have a pot full of flavorful clam liquid, and a pile of chopped clams on the side. Adding the clams immediately back to the pot is a mistake I've often made in the past. Clams are finicky little suckers. They'll go from sweet and tender to overcooked and rubbery in the blink of an eye, and cooking them for as long as it takes to soften a pot of potatoes is a one way ticket to Rubber City.
The solution? Save those clams for the end.
I chop up the clams, transfer them to a strainer set over a bowl (to collect any juices that drip out from inside), then set them aside until just before serving the chowder. If you're using canned or frozen clams, this is even easier—just dump the clams straight in during the last minute or two of simmering.
Now comes the real deep philosophical questions. How do you thicken a chowder properly? Currently, I'd been using a roux-based option. That is, a little flour cooked in the rendered bacon fat used to bind together and thicken the chowder as it simmers.
It's a method that works, if a smooth, homogenous liquid is all you're after. But it also creates that "award-winning" sludge effect, where the chowder becomes so thick and goopy that the flavors—those delicate flavors of clam and pork—are muddied. There has to be a better way.
My next thought was to use the thickening power of potatoes to act as a binder. I knew that starchier potatoes like russets are more likely to break down into a broth than waxier potatoes like reds or Yukon golds, but I gave all three a shot.
Russets were the way to go. They not only thicken the best, but they also have the most tender, potatoey texture in the finished dish. That said, with the elimination of the roux, none of the chowders came out particularly successfully. They inevitably ended up with a greasy, broken appearance and an off-putting curdled texture, like this:
Why does this happen?
Well a chowder (and all non-non-fat dairy, for that matter) is what we call an emulsion; It's a stable mixture of two things that generally don't like to mix very well, in this case water, and fat derived both from the milk/cream, and from the pork. As a general rule, fat molecules like to stick together, while water molecules like to push them as far away as possible. In order to get a smooth, creamy chowder, you need to figure out a way to get them to play nicely together and integrate.
When you pour your milk out of the carton, it comes out as a homogenous, creamy mixture. This is because it's gone through a process called homogenization, in which the the milk is forced at high pressure through a super-fine mesh. This breaks the fat into ultra-tiny droplets, each one of which gets completely surrounded by water molecules, preventing them from rejoining.
Think of the fat as a small group of 49ers fans stuck in a bar in Baltimore. Let them in as a group, and they'll stick together. But let them in one at a time, and it becomes much more difficult for them to find each other, leading to a more homogenous mix in the bar.
Now, let's say that a few of those 49ers fans happen to find each other, forming a small group. Suddenly, that group is much more visible to the rest of the 49ers fans, causing them to get drawn towards it. Eventually, you'll find that very rapidly, your balanced mix is broken, your 49ers fans once again forming a distinct blob in the sea of Ravens fans.
Similarly with an emulsified liquid, disturbing this careful mix even slightly—by, say, heating it—can cause the fat to rapidly separate out from the liquid. What's worse is that once a bit of fat starts to coalesce, it can quickly trigger all the fat to coalesce. So how does one keep an emulsion stable?
One way is to use a roux, which adds flour particles to the mix that physically impede fat droplets from coalescing. But we've already eliminated that option.
What about using the potatoes better?
At first, I tried adding a few very thin slices of potato to the mix, figuring they'd break down into individual starch granules relatively rapidly in the broth.
It didn't work. The chowder was still broken.
Alright, what if instead of waiting for the potatoes to break down naturally, I give them a bit of mechanical aid?
I cooked up another batch, this time forcing the potatoes through a potato ricer and whisking the resulting puree into the broth.
No good. The broth was lumpy, off-puttingly grainy, and to top it off, still broken.
Next, I figured that perhaps my cooking method had something to do with the broth constantly breaking. I know that vigorous heating can cause cream to separate. I also know that the exact ratio of cream to milk, and when in the process the cream is added can have a big impact on how its fat and water content behaves.
I attempted a dozen more versions, adjusting milk to cream ratios (broken)...
...starting some with just milk and finishing with cream (still broken)...
...using slightly lower amounts of roux (pasty tasting up until the roux is nearly eliminated, in which case, broken)...
...to using only broth to cook the vegetables and finishing with cream and milk...
...and all the variations in between.
Failure after failure after failure.
It's not that any of the chowders were bad, per se, certainly the flavor of the broth was superior to the vast majority of restaurant versions, and the texture of the clams and potatoes was spot on. It's just the liquid that suffered appearance and texture-wise without the roux to hold it together.
Then I realized: Perhaps preventing it from breaking is not the way to go about this. Why not just let the darn stuff break, and fix it later?
For my next batch, I made a chowder using the most succesful technique I had attempted thus far, cooking the potatoes and vegetables in milk and adding the cream at the end. This time, instead of just stirring the chopped clams into the broken end result, Instead, I strained the chowder through a fine mesh strainer and dumped the liquid into my blender, figuring that the violent mechanical action of the blender should be powerful enough to break up those fat droplets, as well as to pulverize a few of the potato cells that may have made their way in there, releasing their starch and helping to keep the mixture homogenous.
It worked like a charm. What came out of the blender was a rich, creamy, perfectly smooth liquid that tasted of clams, pork, and dairy. Not too thick, not too thin, not pasty in the slightest. I poured the liquid back over my strained solids, added the chopped clams, reheated the whole deal, and season it.
Am I overcomplicating things here? Perhaps. But I don't think so.
Indeed, I believe that if a traditional dish can be improved using modern techniques and equipment while still maintaining their historic and cultural core, then it is our duty to do so. Chowders have been changing steadily for the past several hundred years, which, incidentally, means that anyone who tells you "that's not real clam chowder" or "chowder needs this or that" is, frankly, full of it. Why should we now choose to freeze chowders in time, when more than ever before, we have an understanding of the hows and whys of cooking?
What ended up in my bowl was more than just the platonic ideal of my childhood Cape Cod memories, it was a dish with a real sense of history about it. Some folks have tried to argue that barbecue is the only true regional American cuisine; The only dish with an identity in both time and place. Well I have a bowl of chowder here that begs to differ.
The only detail remaining? Oyster crackers. Chowder needs oyster crackers. It simply wouldn't be a real clam chowder without'em.
Get The Recipe!
About the author: J. Kenji Lopez-Alt is the Chief Creative Officer of Serious Eats where he likes to explore the science of home cooking in his weekly column The Food Lab. You can follow him at @thefoodlab on Twitter, or at The Food Lab on Facebook.