The Food Lab Lite: Butter Beans with Kale and Eggs
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After roasting a suckling pig a few weeks back, I found myself in possession of far more pork bones and scraps than any reasonable person would know what to do with. Some of them went into a batch of boiled bone broth which Chichi made. Other scraps turned into a stewed pork filling for arepas (stay tuned for a recipe). But at the end of the week, I
Well honestly, nothing goes with pork like beans. The greatest pork and bean dish I've ever had was in Toledo, Spain, where suckling pigs roasted in a wood-fired oven were served alongside a large cazuela filled with judias—a fat, white kidney-shaped relative of the butter bean or lima bean—cooked into a porky, tomatoey stew. Large and robust, they had a perfectly creamy texture and deeply porky flavor. Definitely something worth replicating at home.
You may not be able to find true judias around here, but large lima beans are of the same family and will work just fine. The key to perfectly textured beans is to brine them overnight. Despite the fact that some older books (and chefs) will tell you not to salt your beans until after they're cooked lest you end up with tough skins, salt actually helps bean skins soften properly.
Take a look at this picture which I'm stealing from my article on The Best Chili Eve without my permission (I dare me to report it):
See how nice the ones on the right look compared to the left? Beans contain ions of magnesium and calcium in their skins that act as backup dancers—the supporting act that makes sure the skins stand tall. Soak them and cook them in salty water, and those magnesium and calcium ions decide to take a break, giving the role instead to their sodium ion counterparts.
And as anyone who's ever been to the ion ball can tell you, sodium ain't a dancer. With magnesium and calcium out of the way, the bean walls become much more tender, allowing them to soften at just about the same rate as the bean interiors.
So what does inhibit beans from softening? Acid. The lower the pH of the cooking liquid, the slower the softening reactions become. It's for this reason that a dish like, say, Boston Baked Beans takes overnight for the beans to soften in the acidic, molasses, tomato, and vinegar-laced environment.
We can use this fact to our environment by controlling acidity to halt our beans in their tracks as they cook. As soon as the beans are tender, I add a can of tomatoes to the mix, increasing acidity, and letting me simmer the beans a bit longer with a bit of roughly chopped braising greens. This also lets me cool the beans and reheat them a few days later to make the most of their flavor (they just get better and better as they sit).
If you still haven't had enough pork, you can serve the beans with a pork chop or perhaps a good sausage. I like serving mine with some perfectly boiled eggs drizzled with plenty of olive oil, good crunchy sea salt, and black pepper.
By the way—if you don't have suckling pig leftovers, a hunk of salt pork or even bacon will work just as nicely to flavor your beans.
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About the author: J. Kenji Lopez-Alt is the Managing Editor 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.