How to Make Creamy Asparagus and Tarragon Soup (No Cream Required)

[Photographs and video: J. Kenji López-Alt]

Don't get me wrong: I've got nothing against cream soups. Cream of mushroom. Cream of spinach. Cream of chicken. I love all of them from time to time. But the thing about cream soups is that dairy fat has a way of coating the tongue and dulling vegetable flavors. A cream of asparagus soup might taste like rich, creamy asparagus, but you'd never describe it as bright. If you want a really bright yet creamy vegetable soup, you've got to get rid of that dairy fat.

So how do you make a super-creamy soup with no cream at all? There are a couple ways to get there. Sometimes I'll use bread to thicken my soups, as in this 15-Minute Tomato Soup. The other technique is using a classic French preparation called velouté. The word comes from the same root as velour, and, just like a neon velour tracksuit, velouté is smooth, suave...let's just go with velvety and bright.

In classical French cuisine, velouté is technically a sauce made by thickening stock with a butter- and flour-based roux. Think béchamel with stock instead of milk. These days, if you see the word on a menu, it's more often than not referring to a velvety, satiny soup with relatively little to no dairy fat.

I start my asparagus/tarragon version by sautéing aromatics in olive oil. For sweet asparagus, I prefer the mild flavor of spring leeks to onions. Celery or garlic might be common choices here as well, but I decided to use a thinly sliced bulb of fennel in order to reinforce the anise flavor of the tarragon.

I sauté the vegetables with a pinch of salt in order to help draw out moisture, then, once they're fully softened, I add a couple tablespoons of flour, stirring it until it's blended with the oil in the pot. Next, I pour in a few cups of chicken stock. You could also use vegetable stock, but make sure to use a homemade one; store-bought vegetable stock is almost universally terrible.

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Once it all comes to a simmer, I add some chopped asparagus and a handful of minced fresh tarragon leaves. I tried making a version of the soup in which I sautéed the asparagus before adding the stock, but I found that it didn't really offer a flavor advantage, and resulted in a soup with duller color.

To make things extra fancy, I like to pull out a few asparagus tips after just a minute of simmering, when they're still bright green and crisp. They make a great garnish for the finished soup. I continue simmering the rest of the asparagus until it's tender, just a few minutes longer, then hit it with a squeeze of fresh lemon juice to brighten it up.

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If you want it perfectly velvety-smooth, you can transfer the soup to a powerful countertop blender and let 'er rip, passing it through a fine-mesh strainer afterward. If a still-pretty-smooth-but-a-little-more-rustic purée is okay by you, then a good handheld immersion blender will do the trick, with the added advantage that you can purée the soup right in the pot. (Just be careful of splash-back. I coated my counter and shirt in green slime, Double Dare–style, at least once while developing this recipe!)

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Like fresh asparagus itself, this soup is one of those that are best eaten right after they're made. It cooks so quickly that the purée should still have a vivid green color. It'll still taste fine if you chill it and serve it the next day, but it'll dull to a drab yellowish green by the time you've reheated it.

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I like to garnish my soup with more chopped tarragon, some of the wispy fronds from the top of the fennel, the asparagus tips, a drizzle of olive oil, and just a touch of crème fraîche.

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Okay, so I guess crème fraîche is technically dairy fat. Sue me.