I picked up the nasty, black, almost-starting-to-shrivel things from the fruit bowl on the kitchen counter and was about halfway to the garbage when I was stopped short by my wife's sudden and very loud cry: what are you doing?!
What do you mean, what am I doing, dear? I'm throwing out these rotten plantains that now look more like something produced by the dog than something we should be keeping in the good company of our perfectly respectable grapefruits and mangoes.
Wrong choice of words. My wife proceeded to explain to me just how carefully she had been coddling those plantains, waiting for days and days until they were at just the right level of blackness (that would be pitch black and right on the cusp of starting to shrivel) so that they would be of optimal sweetness when we finally fried them.
I'm glad she caught me when she did. As someone who loves a good salty-sweet snack, fried ripe plantains represent one of the pinnacles of the form.
Truth be told, I'd been enjoying maduros* ever since the first time her Aunt Gloria made them for us many years ago, though I never bothered to peek into her kitchen to see how she did it. Soft and tender with a lightly greasy exterior and a sweet, caramelized flavor, they don't have the crispness you may expect from a starchier fried food, but that's part of their appeal.
*It literally means "mature(s)," and leads to humorous flubs in menu translations in Colombia
See, as plantains mature, their starches slowly convert into sugars and enzymatic reactions lead to the formation of many aromatic compounds that aren't present in their green or yellow forms. It's these starches that set up and give fried foods crispness. So while a fried green plantain (known in Colombia as a patacón) is extra crisp but relatively bland, a fried black plantain is packed with flavor with a softer, more custard-like texture.
Just like bananas, apples, and tomatoes, plantains ripen better at room temperature in a relatively enclosed environment, like in a bowl with other fruits, or inside a paper bag. Plantains give off ethylene gas, the natural trigger for ripening. The more concentrated that gas, the faster the fruit will ripen. From green to black, a plantain can take over a month to fully mature in a bowl. Put them in a paper bag and the time will be cut down to a matter of weeks or even days.
Luckily, most good Latin markets will sell plantains at a variety of maturity levels, so ripening need not take that long.
The trick to great maduros is to cook them relatively slowly, giving the sugars plenty of time to caramelize and get extra sweet without giving the plantain a chance to dry out. To do this, I shallow fry them, first starting in moderately hot oil and cooking them just long enough that they develop a thin pale golden brown pellicle on their exterior to keep them from sticking together. From there, I lower the heat and cook them slowly until deep brown and completely tender throughout.
Sprinkled with just a little salt, they are excellent as is, but if you want to go a little more balanced, a little more complex in your snacks (and who wouldn't?), they are miles better when some of that greasy, sweet-and-salty, custard-like flavor is cut with a sharp, acidic sauce. In my wife's aunt's place, that sauce would be a simple tomato and onion Ají, the Colombian equivalent of a Mexican salsa. But [shhhh...] I secretly prefer my plantains with a Puerto Rican-style Mojo, a parsley and garlic-flavored rough sauce very similar to Italian-Style Salsa Verde. In this version, I add a handful of mint leaves to the parsley for an added dimension.