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It's always important to question your initial impulses. Just imagine if Lincoln had started the Gettysburg Address with his original text, which is believed to have been "These past 87 years have been one hell of a slow-motion train wreck, amiright?" Or if Martin Luther King had gone with the first draft of his March on Washington speech, tentatively titled I Slept Poorly Last Night. And think of the mess scientists would still be cleaning up today if Heisenberg had published his Absolutely-Damned-Certain Principle.
I'm proud to add this soup to the list of things that, once rejiggered, changed the course of history...or, in this case at least, changed the course of your first course. That's because what I originally wanted to do was make a roasted butternut squash soup, with its sweet, deep, earthy flavor. But then I thought, That's what everyone else does. How can I approach this soup in a different way?
Then I remembered one of my favorite squash preparations, kabocha no nimono, a Japanese dish of winter kabocha squash poached in a light dashi-based broth. Unlike roasting, which enhances caramelization of the squash's sugars, poaching plays up its nutty, savory flavors. It's a refreshing change of perspective on what squash can taste like.
For this recipe, I used red kuri squash, a Japanese variety that is often available at farmers markets, but kabocha or even butternut will work in its place. Kuri squash has a distinct chestnut-like taste, with a slightly starchy texture.
For kabocha no nimono, the skin is usually left on the squash. For this soup, though, I peeled the squash, since the skin would only gunk up the texture once the squash was puréed. I highly recommend a Y-peeler with a sharp blade for this job; as you can see in the photo, I had to brace the squash against myself while peeling.
Just like in the nimono preparation, the base of this soup is dashi, the Japanese stock made from intensely savory ingredients like shaved bonito flakes and kombu seaweed, both of which are loaded with the glutamates responsible for umami flavors.
For years I read about the lifelong quest of Japanese chefs to master dashi making, and, frankly, it intimidated the heck out of me. But, as it turns out, basic dashi is extremely easy to make. I borrowed the shortcut method that Kenji uses for his miso soup recipe: Simply simmer the kombu and bonito flakes in water for five minutes, then let them stand for another five minutes before straining. It's easier than almost any other stock I know of.
To make the soup, I used the basic technique for any smoothly puréed vegetable soup, first sweating aromatics like leek, carrot, garlic, and ginger in oil, then adding the squash and just enough dashi to cover. The whole thing simmers until all the vegetables are fully softened.
You can blend everything in the pot if you have an immersion blender, or you can transfer it to the jar of a standing blender and purée it in batches. One word of warning for any time you're blending hot liquids: If the blender is set to high speed, a blast of steam can form immediately, strong enough to blow the top off and send hot liquid spraying everywhere. To avoid burns and a soup-splattered ceiling, I recommend setting the blender to its lowest speed and removing the hard plastic cap in the center of the blender's rubber lid, then placing a clean kitchen towel over the lid. The opening should act as a vent for steam, while the towel catches any splatter. Once it's going, you can crank the blender up to high speed without any problems.
A couple of tablespoons of miso added at this point build on the squash's savory flavor, adding extra depth and rounding out the flavor of the soup considerably, while a little lemon juice adds brightness.
I used a high-speed blender here, which is powerful enough to completely transform the vegetables and liquid into a purée with an incredibly silky texture. If yours isn't quite so powerful, you may want to press the soup through a fine-mesh strainer after blending, or you can just take the easy road by embracing its more rustic texture.
Most likely the soup will be too thick at this point—that's a good thing. It's far easier to thin a soup than it is to thicken it once it's been puréed. Just return the soup to the pot, add enough water to create a satiny-smooth, pourable consistency, and adjust the seasoning.
For a finishing touch, I whipped up a garnish made from diced apples, sliced scallions, minced fresh ginger, and sesame oil. It may seem safe to assume that a garnish like this is optional, but it's not. The apple adds bursts of fresh sweetness to what is otherwise a very savory soup—it really needs it to work.
To prevent my apple from browning, I used the salt-soaking method, which I've found to be the most effective out of several easy home methods using basic ingredients. This way, you can dice the apple and prepare the garnish while the vegetables are still simmering in the pot and have it ready when it's time for serving.
For one last (optional) touch, I sprinkled on a little shichimi togarashi, a Japanese spice blend made from chili powder, dried orange peel, black sesame seeds, and ginger.
I know I can't speak for the rest of you, but after this squash soup, I'll never think of the dish in quite the same way again.
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