Lettuce Soup Recipe

Leaf lettuce, leeks, a savory broth and a dollop of Greek yogurt are all you need to create a delicate lettuce soup that’s excellent hot or cold.

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Thanks to a warm and rainy early Spring, my garden is going crazy already. The zucchini plants are enormous, the peas and cucumbers are climbing skyward, and the herb garden is beginning to look like a  jungle. I even have a half dozen tomatoes the size of golf balls, and it’s not even summer yet!

But it’s the lettuce patch that’s overwhelming me right now. I bought a seed packet that promised a 3-season mix and planted it in early May. We like lettuce, and I loved not having to sow more seeds every two weeks to keep us eating our greens throughout the growing season. But it turns out the seed packet lied. Oh, there’s some green leaf lettuce and a few Romaine heads, but more than that, there’s red leaf lettuce. Tons of red leaf lettuce.

That’s not a bad thing — it’s delicious in salads, but even making two huge salads a day hasn’t made a dent in my lettuce patch. And, unlike Romaine or Boston or buttercrunch lettuce, the red leaf stuff doesn’t work to make wraps or lettuce boats.

What’s a girl to do?

Well, when life gives you too much lettuce, it’s time to get creative, and that’s how I came up with this lettuce soup recipe. I figured it couldn’t be too different from making spinach soup, though I didn’t want to load it down with cream or cheese. Lettuce is sweet and delicate on its own, but spinach has a bit more tang to it — so I wanted to come up with a soup that capitalized on the delicate flavor.

How to Make Lettuce Soup

Lettuce soup is easy peasy to make, too — though there are no peas involved. Instead, I decided to pair the sweet taste of lettuce with leeks which brought some bite and another layer of flavor to the mix. If you haven’t cooked with leeks much before, there are a few tricks to cleaning them.

Step 1. Triple Wash Sliced Leeks to Remove Grit

Leeks are grown by burying them in the dirt. You start them in the late fall or early Spring, depending on your gardening zone, in an extra-deep planter with just a few inches of soil. As they grow, you add more dirt, so only the green tops appear above the ground line. They’re ready when they’re about 2 feet tall, with about one foot of green tops above the edge of the planter.

Thanks to that growing process, they’re full of dirt — not just on the outside but between the layers. So, to clean leeks, you slice all but a couple of inches of the green tops off, then slice the root end away and cut the leek down the middle lengthwise.

Peel away the outer, tough leaves. They taste nasty and won’t cook properly, anyway. I toss mine into the compost pile so I don’t feel too bad about discarding them. If you feel guilty, there are many ways to use leek leaves, including wrapping fish before baking.

Anyway, slice the white parts crosswise and then wash them. Get your hands in there and swirl them around in the water to dislodge all of the soil. Even the leeks you buy in the grocery store will be gritty, so it’s always a good idea to repeat that process three times or until you stop seeing grit in the water, whichever comes last.

Step 2. Cook Leeks Until Soft

Cook those leeks in 2 tablespoons of your preferred fat. I went with a really good extra virgin olive oil. You could use coconut oil if you’re into that, but it may affect the flavor. I’d suggest something more neutral if you don’t like olive oil.

Step 3. Add Broth

Once the leeks start to soften, add 1 cup of chicken broth and bring it to a simmer until they are very soft — at least five minutes. You can use bone broth if you like, or go vegan and use vegetable stock.

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Step 4. Stir in Lettuce

Add the lettuce one handful at a time, stirring between each until the previous handful has softened. This recipe uses a lot of lettuce — exactly what I wanted! I used 16 ounces of it to make three large bowls of soup. And for the curious, a full pound of leaf lettuce like that is enough to fill a grocery-sized brown paper bag. It was so much.

If you want to make more or less, adjust the amount of the other ingredients. You can do the math. I have faith in you.

When you’ve got all of the lettuce added, bring it back to a boil, then turn down the heat. Simmer for another 5 minutes until everything is nice and soft. Then, remove it from the heat and give the whole thing a couple of minutes to stop steaming. Once it’s cooled a bit, taste and season it if you like. I found the flavor was perfect thanks to the chicken stock, so I didn’t need to add any salt, just a very tiny pinch of ground white pepper.

When the flavor is to your liking, transfer the contents of your soup pot to a food processor or blender. I’d love to tell you to use a stick blender in the pot, but I tried that, and it just started creating a stringy mess.

Step 5. Blend

It’s much easier to run this soup through a machine. If you’re using a blender, pop the clear button out of the lid and lightly cover the hole with a towel so the steam can escape without burning your hand. If you’re using a food processor, as I did, it’s never a bad idea to stick a towel over the top, just in case.

Divide the soup between bowls (3 if you’re using large bowls for a main course soup or 6 if you’re serving it as a side), then add a dollop of Greek yogurt on top and chiffonade some lettuce to sprinkle on top for garnish. Or don’t. It’s all good.

This soup is perfect served warm but, much to my surprise, is also light and delicious when served cold. It would be an excellent accompaniment to grilled chicken or baked fish (see, that’s how you use those outer leek leaves) or a nice meal with a hunk of ciabatta bread.