Tarragon may be one of my favorite herbs, which is actually kind of odd given how much I dislike most licorice-flavored foods. Whatever the explanation for that conflict, I wanted to try to make tarragon work in a pesto-like sauce. The risk, though, is that large quantities of tarragon can be too potent (in fact, large doses of tarragon have a mild anesthetic effect, causing a mouth-tingling, numbing sensation).
To get just enough of the tarragon flavor without it overwhelming the sauce or causing strange oral sensations, I mixed it with a larger quantity of parsley, which is mild enough not to upstage the tarragon. I also kept this sauce very simple to give it a very clean flavor, leaving out the nuts and cheese you'd typically put into a pesto. Some folks may object that it's no longer a pesto without nuts and cheese. To that, I say it technically stopped being pesto as we know it as soon as I changed the herbs. For just the faintest hint of warm chili heat, I also blended in a pinch of espelette pepper, which is mild and fruity in flavor.
Instead of serving this sauce on pasta, I decided to dress a potato salad with it instead. I used incredibly sweet young Yukon Golds that I picked up at the farmers market, and tossed in some pickled red onion and pitted Kalamata olives.
A quick twenty-minute bath in red wine vinegar transforms the onions, from raw and potent (above), to more tender and mild (below)—even the color of the onion changes.
If you don't feel like making the potato salad, this tarragon pesto would be great on steamed or roasted fish, chicken, and boiled eggs.
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