All the recipes that say cilantro is a good substitute for culantro—they’re lying to you. That’s it. If you can’t get culantro, recao in Puerto Rico, don’t do what you’re thinking right now. In fact, don’t think it. That way lies madness.

Simple fact No. 1: Cilantro is a pleasant herb. It’s aromatic and has a tiny bite that makes us think there’s something exotic about it, but we can’t quite place what makes it special.

Simple fact No. 2: Recao, or culantro, is as strong as it is unmistakable. It is unapologetically intense. It practically carries a knife. It’s the James Dean of spices.

In Puerto Rico, recao finds its most familiar home in the sofrito that forms the flavor bed for so many dishes. For sofrito, the recao cozies up with onions, garlic, bell peppers, and ají dulce. All pulverized and fragrant, sofrito gives you the confidence to cook anything, because if this is just the beginning—and what a brilliant one at that—surely, surely, you must be doing something very wrong (or perhaps you are fundamentally a bad person and deserve no good) if you wreck the rest of the recipe.

But focus now: recao. This gorgeous serrated blade is, it is true, related to cilantro. They are family. Literally, in the scientific classification, they are identical up to the family file. But there they part. So you see why people are always saying they are cousins. That said, I feel people (and hard, irrefutable science) are too quick to ascribe importance and similarity to DNA. I think of them as maybe related in the manner of in-laws. Not a blood relative, but around enough to pick up some whiff of family traits. And in this particular case, whiff-ability is a huge deal.

To know how refreshing and pleasing cilantro is, chew a piece and muse on it. To know anything about recao, simply find a field in which you suspect it is growing and you’ll know if it’s there. The first thing you’ll be is surprised. The Caribbean is full of strong-smelling things, but this is a sharp is-it-or-isn’t-it-mint scent. Makes you think very cool, un-equatorial thoughts. Some researchers think the flavor of recao is between eight and 10 times as strong as cilantro. When anything is regarded in such significant multiples, surely it is something else and not really on a continuum. As we know all too well, “Oh what a nice drizzle” and “This is a storm” are in no way comparable.

The really big deal about recao is how dramatic it is. It is sharp and dense. It can burn the way only cold burns. It is absolutely nothing like a habanero burn. I don’t know if the taste has ever been artificially replicated, but I would go into a lab thinking I needed a lot of mint, some unspecified Indian spice, and the spirit equivalent of my body weight in cinnamon candy. See that? It’s all hot-cold head-rush stuff.

Puerto Rico does not claim sole proprietorship. It can be found in other Latin American, Caribbean, and Asian recipes. Yes, you can, with a great deal of foraging, find it in some places in between. But more likely the grocer will try to get you to buy into the cilantro/culantro bit. I refer you to paragraph 1 of this story.

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