Beans, and baked beans in particular, have been a staple throughout New England since the time of the Pilgrims, not to mention in the rest of the colonies and the world beyond. In Tuscany, they eat fagioli al fiasco; in Languedoc, it's cassoulet; in Portugal and its former colonies, feijoada. And yet, somehow, Boston got singled out with the nickname "Beantown"* for its love of the local version of the dish. (Although, to be fair, one Italian nickname for a Tuscan is mangiafagioli, or "bean-eater," so there's that.)
* A name that no true Bostonian would ever self-apply.
What are Boston baked beans? The short answer is that they're small white beans (usually navy beans), slow-cooked in an oven, hearth, or ember-filled hole in the ground with molasses, salt pork, black pepper, and maybe a touch of mustard and onion until they form a thick stew, rich with a deep color and caramelized crust. Those are the ingredients my 1939 copy of The New England Yankee Cookbook calls for; it's what my 1914 copy of Household Discoveries & Mrs. Curtis's Cook Book describes; and it's what The Fannie Farmer Cookbook instructs as well (along with adding a couple of tablespoons of sugar).
The long answer, though, is that it can be difficult to fully differentiate them from other baked beans of colonial New England, including the famed baked beans of Maine.
Some say Maine's beans are made with a higher ratio of salt pork, while my copy of American Food: The Gastronomic Story quotes a Lewiston, Maine, newspaper as saying that the biggest difference is that Maine's baked beans are cooked just enough to tenderize the beans, but not so much that they melt down into a thick sauce. "They never wholly assimilate or mash...in Maine. You do get in Boston a sort of brown paste with small nubbly particles in it, dejected in appearance. It should be called 'bean butter.'"
That's a little harsh, and, since none of the other recipes I read advise cooking Boston baked beans to the point of making a paste, I think it's safe to assume that, fed by a bit of regional competitiveness, that Maine newspaper was exaggerating just a little. Still, if we're willing to allow that there might be a grain of truth to the quote, it can help explain a few things about some of the Boston baked bean recipes out there today.
See, the thing with beans cooked in molasses is that they tenderize very, very slowly (more on this later). Even after leaving them for hours in the oven, you can end up with individual beans floating in a thin broth. But Boston baked beans should, at the very least, be coated in a thickened, glaze-like sauce. Some recipes resort to adding tomato paste or ketchup to thicken the broth, and I'll admit that, in the process of testing this recipe, I considered doing that more than a couple of times myself.
In the end, I decided to stick firm to tradition and find a way to get my beans soft and my sauce thick without relying on modern add-ins. That meant a baked bean recipe with nothing but beans, molasses, pork, onion, and mustard (and, okay, a couple of aromatics).
When colonists first observed northeastern Native Americans preparing baked beans, what they likely saw being poured into the bean pot was maple syrup, which resulted in a calorie- and protein-rich meal that could warm stomachs and provide needed sustenance through the brutal winter months. In some parts, like Vermont, maple syrup is still used today. But with the slave trade and, more specifically, the triangular trade that circulated slaves, sugarcane, rum, and other goods throughout the Atlantic, the town of Boston was awash in molasses,** and so, too, were its beans.
** Quite literally: In 1919, a massive molasses storage container ruptured in Boston's North End, with 21 people and several horses killed by the flood...which was apparently not quite as slow as molasses.
The thing with molasses, though, is that it significantly slows down the rate at which beans soften during cooking. First, the slightly acidic pH of molasses, according to McGee, makes the pectins and hemicellulose in the beans' cell walls more stable and less prone to dissolving; second, the sugar in the molasses strengthens the beans' cell walls and slows down the rate at which their starch absorbs water; and, finally, the calcium in molasses steps in to further strengthen the beans' cell walls.
Back in the day, when masonry ovens retained plenty of heat throughout the night, this was a great perk: You could throw a pot of beans in the oven (or in an earthen hole, if you were cooking outdoors) in the evening and open it in the morning to find something that wasn't mush. Today, though, the molasses creates a minor challenge. Either we follow in our forebears' footsteps by sticking a pot of beans in the oven overnight, or we need some kind of trick to cut the cooking time slightly.
Well, I tried a few tricks, as well as the overnight method, and found that you really only have a couple of good options.
My favorite beans by far were the ones I cooked start to finish in the oven. I first soaked them in salted water for several hours, drained them, then mixed them with all the other ingredients in a Dutch oven. With the cover on the pot, I slid it into a 250°F oven before going to bed. Thirteen hours later, I had the most beautiful pot of Boston baked beans imaginable. They were silky and tender, with a richly caramelized and browned crust on top and a thickened, sweet-savory sauce that coated each and every bean—the thickening was the result of bean starches leaching out into the cooking liquid during all those slow, sleepy hours. Most of the beans remained whole, or mostly whole, but some broke down, which enriched the sauce—precisely what we want when we don't want to resort to ketchup.
But there are some drawbacks to this method. First, it takes a damned long time. And second, you have to feel comfortable going to bed with your oven on, which you may not for fire safety reasons. (Frankly, I'm not sure I should even recommend it, for liability reasons.) A slow cooker might solve this overnight problem, but without the all-around dry heat of an oven, it wouldn't allow for much of the critically important evaporation and surface browning.
So what about alternatives? I tried making a batch with baking soda added to the pot, which counteracts the low pH of the molasses and speeds cooking time. This led to a pot of mushy, over-browned beans (a higher pH accelerates browning reactions) that lacked the hard-earned flavor of true slow cooking that was needed to make them a success.
Next, I tried a pressure cooker. It was able to soften the beans in about 30 minutes, even with the molasses already mixed in, but what I was left with was exactly what you'd expect from a gasket-sealed pot that prohibits evaporation and browning: too much broth and not enough flavor. Even after moving the pressure-cooked beans to the oven, I wasn't able to get nearly the same browning and evaporation as I did from those cooked for a long time in the oven.
That left one final method, which is the one you'll most commonly see, including in many old recipes: par-cooking the beans in water, then mixing them with the molasses and other ingredients, transferring them to the oven, and cooking for several hours more until done. It's a method that works, but there are a few key steps needed along the way for the beans to come out just right.
Before I move on to the method for making the beans, a quick word on the pork. Traditionally, the cut used is salt pork, which is the salted and cured slab of thick fat that runs along a pig's back. It adds a deep, pure pork flavor to the beans, but you do need to watch out for two things. First, if you use a piece of salt pork that's solid fat, with no stripe of muscle at all, you may want to cut the quantity slightly (say, from a half pound down to a third of a pound or so per pound of beans). If you don't, you can end up with some seriously greasy beans...good if you're a lumberjack, but not great otherwise.
Second, some salt pork comes with plenty of salt still clinging to it. If yours does, you'll want to wash the excess off, lest your beans end up oversalted.
If you can't find salt pork, you can, of course, substitute slab or thick-cut bacon. Since bacon comes from the belly, the cut has a higher ratio of lean muscle to fat than salt pork does. You can stay at a half pound per pound of beans, or you can go wild and bump it up to three-quarters of a pound if you want them extra bacon-y. That's not such a bad thing, since the bacon adds a smoky flavor that's probably not too far off from the taste of the beans back when the Pilgrims cooked them in the flickering embers of a dying wood fire.
If you were to disregard basic fire safety and cook the beans start to finish in the oven overnight, all you'd do is combine all the ingredients in a Dutch oven, cover it, and bake it for hours upon hours upon hours. Toward the end, if they got too dry, you'd need to add a splash or two of boiling water, but otherwise, that's about it. Just remember: I'm not officially recommending this, so if you burn your house down, don't come looking for me.
The safer route is one that allows you to monitor the cooking process throughout.
Step 1: Soak Beans in Salted Water
Kenji recently tested bean-soaking and -cooking methods and found that he got the best, most consistent, most evenly cooked results by soaking the beans overnight in water with one tablespoon of kosher salt per quart (about 15 grams per liter). So that's what we're doing here. Once the presoak is done, drain them well, rinse them with fresh water, and add them to a pot.
Step 2: Precook Beans (With Aromatics!), Then Save the Bean Water
Now top the beans up with enough fresh water to cover by a couple of inches, and add a generous pinch of salt to the pot. (Once again, the salt allows for more even cooking and fewer ruptured beans.)
I always cook my beans with some aromatics, like onion, carrot, garlic, and woodsy herbs such as rosemary, sage, bay leaf, and/or thyme. It's not necessarily traditional to do this for Boston baked beans, but the aromatics always add enough of a flavor boost to all my bean dishes that I see no reason not to do it here as well.
Bring the pot to a gentle simmer, then cook the beans until they're done. I made the mistake early on in my testing of precooking them to just shy of doneness, and the result was an endless baking time due to the powerful effect of molasses. Take my word for it: You want the beans creamy and tender before they even go in the oven.
While the beans are cooking, I prep the other ingredients, cutting the salt pork into large chunks, dicing the onion, and combining the molasses with the mustard, salt, and plenty of freshly ground black pepper.
Molasses is very thick, which makes it difficult to combine with the beans. The solution: As soon as the beans are done, take a couple of cups of the bean-cooking liquid and mix it with the molasses to thin it out. A lot of recipes have you drain and discard the cooking water and replace it with fresh water, but that's a terrible idea. That bean water is loaded with bean starch and flavor, two things you absolutely want to keep in the bean pot.
Step 3: Choose Your Own Adventure (Dump-and-Bake or Stovetop-Start)
At this point, you can go one of two ways. You can combine the beans with the molasses water, pork, and onion in a Dutch oven or baking dish and put it directly in the oven to cook for several hours. Or, you can sauté the pork and onions first, then add the beans and the molasses water, and bring it all to a simmer before transferring it to the oven. The cooking vessel is kept uncovered in both cases, and all you need to do is check the beans from time to time and add some of the leftover bean-cooking liquid (and, when that runs out, boiling water) if the beans on top are drying out too much.
The advantage of the first option is that it requires the least work. And, ultimately, all the browning and the crust that forms on top of the beans add plenty of deep flavor, rendering the sautéing of the pork and onion beforehand mostly unnecessary. But one thing I found beneficial about starting on the stovetop is that it kicks off the subsequent oven cooking at full speed: You can bring the liquid to a simmer much faster on the stovetop than you can in a moderate oven, which means the beans are already chugging along by the time you put them to bake. That leads to faster development of a deep, flavorful browned crust on top, which I think is worth it. Therefore, that's what my recipe calls for, though, if you're in a rush, know that you can skip it.
One important detail: Make sure to add enough liquid to the beans to just barely cover the ones at the top.
Step 4: Oven Time...
Now your beans are in the oven, set to about 325°F. Time to wait.
Has it been a while? Go take a look. If the cooking liquid has evaporated and the topmost beans look like they're at risk of drying out, just add more of the bean-cooking liquid. If and when you run out of bean-cooking liquid, switch to boiling water.
Now go wait again.
Bored? Maybe check on the beans. This is going to be your life for the next four hours or so, if not longer. Mostly, it's just a balancing act between preventing the liquid from getting so low that the top beans dry out, and keeping it so high that those top beans can't develop a flavorful crust.
Once or twice during cooking, I'll even give it a stir, just to submerge the topmost beans and bring some of the ones from below up to the surface. Just like in a cassoulet, breaking the crust and stirring it into the beans gives that flavor deep roots.
During the final hour or so, when the beans have become supremely tender and, hopefully, just a few are breaking apart, you'll want to let the liquid recede without topping it up—remember, the goal isn't bean-y broth, it's saucy beans.
Step 5: ...and Finish
With all that pork fat and cooking liquid, your finished beans may still look a little greasy and brothy at first. A good stir should help emulsify the pork fat, whip up some of the free bean starch, and form a nice glaze. If the beans are too dry, add some hot water—or leftover bean-cooking water, if you still have some—until they're just saucy enough. If they're too wet and you're tired of waiting for them to finish in the oven, you can always bring the pot (assuming you're using a pot) to a simmer on the stovetop to reduce the liquid a little, though this was not a situation I ever ran into while testing.
At this point, adjust the seasoning, adding more salt or fresh black pepper if needed. If the beans are a little too sweet for your taste, you can add a sparing splash of cider vinegar to balance the flavor, though I never felt my beans really needed it. The final stew I ended up with was creamy, rich, and saucy, with a sweet-and-savory balance that was good enough to name a town after.
I was in a Beantown all my own, and it was lovely.