The Food Lab: Easy Red Lentil Soup With Curry Yogurt
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This is not the first time I've written about lentil soup, and it won't be the last. That's what happens when you're married to a woman who loves it just a bit more than she loves you.
In fact, I'm starting to suspect that she loves me only because I supply her with a steady diet of lentil soup. Not that I blame her. It's good stuff, especially when you make it right.
Even though my wife is a firecracker in many respects—don't get her started on South American literature or Buffalo wings—when it comes to lentil soup, she likes to keep it vanilla. I almost gave her a conniption when I told her I made her lentil soup one night and it turned out to be my Vegan Coconut Lentil Soup with Cilantro-Habanero Gremolata. Apparently it's just a bit too flavorful for her.
Even the Vegan Lentil Soup I made her last February was ruined when I sprinkled it with chopped parsley. Oops.
This time, I'm finally doing it right. This soup is very simple, with just a few aromatics that blend together beautifully in the background—it's a decidedly lentil-forward flavor—and a curry yogurt garnish that adds some flavor, but can be added at the table so that my wife can enjoy her bowl completely plain if she'd like. (Weirdo.)
To keep things extra simple, I pulled out the food processor to chop the aromatics. Not only does it make chopping faster, it also lets you reduce them down to a much finer particle size, which makes sweating them out speedier, too.
Scallions (you can use onion), carrot, celery, garlic, ginger, and chili reduced pulverized to smithereens. "What is this, mirepoix for ants?" is the level you're going for. You can do it by hand, but there's no point in owning fun tools if you don't use them, right?
After chopping, they get a quick sauté in olive oil. Their huge surface area to volume ratio causes them to rapidly give up their moisture and start sweetening and developing flavors.
In go the lentils. The tiny red or yellow lentils will cook up fastest. You can use brown lentils as well, but you'll have to increase simmering time by 10 to 15 minutes. I don't have time for that kind of nonsense this week.
Some vegetable stock (if you want it to stay vegetarian) or chicken stock (if you don't), a couple of bay leaves, and a 15 minute wait is all it takes. Don't have anything to do during those 15 minutes? Now would be a good time to try and learn how to run in QWOP.
Or not, actually. Because I guarantee you'll forget about the soup once you get into the never-ending nightmare that is QWOP.
Instead, do this:
Combine some Greek-style yogurt with some curry powder, some chopped cilantro, and some salt. This is the condiment that the big kids are going to add to their soup just before serving.
You can blend the soup with a hand blender if you prefer a chunkier consistency, but for this batch, I felt like taking the velvety-smooth approach.
It's a convenient method, because it also lets you emulsify a bit of extra-virgin olive oil into it, giving it both more body and flavor.
If there's one thing that could improve the food of 99% of home cooks I've ever met, it's regulating acidity. Everybody knows that salt is key to bringing out the flavor in foods, but acidity is almost as important.
Try this: Season your lentil soup with salt and pepper, and take a sip. Now squeeze a couple lemons into it, whisk it up, and taste again. See what I mean? It not only tastes brighter and fresher, but somehow tastes more lentil-y as well, if lentil-y were a word.
Serve the soup with a dollop of the curry yogurt and olive oil, or better yet, let both the yogurt and the soup rest in the fridge overnight. Both of them will develop better flavor with a bit of time.
By the time you read this post, my wife will have already eaten several batches of this soup. I'm hoping that it finally meets with her approval. If you don't hear from me again or I don't respond to comments here immediately, call the police.
About the author: J. Kenji Lopez-Alt is the Chief Creative Officer of Serious Eats where he likes to explore the science of home cooking in his weekly column The Food Lab. You can follow him at @thefoodlab on Twitter, or at The Food Lab on Facebook.