Clean-Out-the-Fridge Soup Recipe

Clean-out-the-fridge Soup

The natural consequence of buying fresh vegetables to eat is that you may end up, at some point, with not-so-fresh vegetables to eat.

However diligent your meal planning, it is difficult to nail it perfectly. And if you leave room for improvisation and sudden crushes in your shopping habits, or subscribe to a weekly produce basket, the end of the week is likely to find you with soft carrots and wilting greens from time to time.

The sturdier produce will keep fine from one week to the next; if you own The French Market Cookbook you’ll find a guide to produce that keeps and produce that doesn’t in the intro section. But for the more fragile vegetables, and if you like to start the week on a clean slate or need to make room for your overenthusiastic farmers market run (ahem), what’s the solution? If you answered “garbage can”, come see me at my desk before recess. The correct answer is soup.

Soup is an extraordinary catch-all for vegetable odds and ends, and it is the easiest and most rewarding way to transform scraps no one really wants to deal with into something warm and inviting. Although it’s hard to truly botch a soup, my years of soup-making experience have taught me that there are a few rules that make the ride smoother and the result tastier.

Choosing your vegetables

Naturally, I am talking about using vegetables that are past their golden days, yes, but haven’t reached the stage of putrefaction: wilted and limp is fine, moldy and mushy-brown is not. And when in doubt, toss it out.

You can, in theory, throw into the soup pot whatever needs using up, but it pays to select your vegetables with an eye towards variety and balance. I enjoy my clean-out-the-fridge soups the most when I’ve used a mix of colors (green, orange, tan, white…) and flavor families (sweet, earthy, verdant, onion-y, aniseed-y…), and included vegetables that grow both above- and below-ground. Some fruits, such as apples and pears, fare well in there too (bananas not so much).

To achieve that, you can of course complement the selection with a few freshly bought vegetables and/or freezer-stashed ones. In fact, if you find yourself with clean-out-the-fridge soup material in too small a quantity to actually make clean-out-the-fridge soup, or if you’re simply short on time, you should clean and chop those vegetables as if you were about to cook the soup, and stash them in the freezer instead.

To give you an example, my most recent edition this past Monday contained a few stalks of (wilting) Swiss chard, a quarter of a kabocha squash (the rest had been roasted), a small bunch of thin (and limp) carrots, the outer leaves from a head of cauliflower (stashed in the freezer), the stalks from a bunch of curly kale (leftover from making cheesy kale chips I’ll soon tell you about), a few bulbs of baby fennel (freshly purchased), a good red onion, a couple of potatoes, the end of a bunch of chives, parsley stems, and some tarragon.

The vegetables should be cleaned thoroughly — no need to dry them as they’ll just be wet again in a moment — and cut into even-sized chunks. Medium pieces — say, 2-cm (1/2-inch) cubes or slices — save chopping time and work fine if you plan to purée the soup. If you prefer a chunky, non-puréed soup, aim for a finer dice.

Clean-out-the-fridge Soup

On texture

Such mixed vegetable soups benefit from a bit of starch to make them both velvety — the French don’t call them veloutés for nothing — and more satisfying. For this purpose you can throw in some potatoes (regular or sweet; I use organic and keep the peel on), some pink lentils or split peas, or the stale end of a loaf of good bread.

If you prefer to avoid starches in your diet — hello, paleo readers! — you can skip this and use nut butter or coconut milk (see below) to achieve creaminess.

Conversely, use highly fibrous ingredients with caution: I once thought it a good idea to include the tall and very bushy fronds from a bunch of fennel, but my immersion blender could never quite vanquish them and my soup, while delicious, was a bit hairy for my taste.

Flavor boosters

Along with the vegetables you can add some garlic and any kind of spice (cumin, cloves, fennel seeds, coriander, fenugreek, peppercorns, chili pepper, whole or ground) or herb you like. Dried herbs (thyme, rosemary, oregano) can be added early on, while fresh herbs (parsley, chives, cilantro, tarragon, chervil, basil) should be added at the last minute, just as you process the soup.

The liquid you use in the soup is of importance, too. In a pinch, water will do, but if you have homemade vegetable or chicken stock on hand, this would be a fine time to use it. I no longer bother with bouillon cubes or powder as I don’t think they add much to the conversation, but the choice is yours.

My secret trick is to ask for extra cooking juice when we buy a chicken from the rôtisserie, if I can remember to bring along a clean jam jar for that. I keep it in the fridge and use it for my soups: the layer of fat that collects at the top is used to start the cooking, and the rest of the congealed, flavorsome juice is like concentrated chicken stock.

You can also go for an Asian flavor profile and add a can of coconut milk. You can then complement that with a thumb-sized piece of fresh, grated ginger and/or a stalk of lemongrass (which can be stocked in the freezer and minced without thawing), and maybe some cilantro or mint as a garnish.

Cooking the soup

If you abide by the classic soup-making method, you’re supposed to sweat your aromatics in some fat first, and add vegetables in order of their optimal cooking time. But my goal with the clean-out-the-fridge soup is to streamline the process and to make it as hassle-free as possible, so I don’t worry too much.

When all the vegetables are clean, I start heating some fat (olive oil, or rendered animal fat if I have some saved) in my cast-iron cocotte. I add the onions and spices first with a bit of salt, to soften and toast while I chop the rest of the vegetables. These I add in as I go, stirring every once in a while. I do this over moderate heat so nothing burns if I forget to stir.

I then add whatever cooking liquid I’ve chosen to use, and because that’s usually not enough, top it up with fresh water to just cover the vegetables. I add salt (about 1/2 teaspoon per liter/quart of liquid, less if the stock is already seasoned), I increase the heat, cover, and bring to a simmer. After a few minutes, there’s usually some foam gathering at the surface, which I skim off for good luck.

I let this simmer 15 to 20 minutes, enough for the longest-cooking vegetables (such as carrots and potatoes) to become tender, easily pierced with the tip of a knife. I find the other, shorter-cooking vegetables don’t suffer significantly from the added cooking time, and my life is made immeasurably easier.

Finishing and serving the soup

I let the soup cool just a bit, fish out any woody herb stems, then whip out my immersion blender and purée the soup thoroughly. It’s safest to wear an apron and long sleeves for this, but if you keep the head of the blender submerged at all times, the splatter is minimal to nonexistent.

Although I haven’t owned one in years, I understand a regular blender would work even better. Food processors are less ideal as they are not watertight and you need to work in small batches, which goes contrary to the hassle-free premise of this soup.

This is the time to adjust the seasoning with salt, and add a touch of acidity, too, in the form of lemon juice, your favorite vinegar, or maybe a spoonful of mustard. If you find your soup tastes a little dull, adjusting both those dials (salt and acidity) should do the trick.

You can serve the soup as is — no need to present it as a clean-out-the-fridge soup if you doubt your audience will be enchanted by the thought — or spruce it up with your choice of:

  • a scatter of (fresh and perky) chopped herbs,
  • a drizzle of oil,
  • a spoonful of cream, pesto, gremolata, nut butter, or tahini sauce,
  • some croutons (bonus points if they’re homemade to use up stale bread).

If you’re feeling extra fancy, you could finish the soup French onion soup-style: pour it in heatproof bowls, top the soup with a slice of bread brushed with a little white wine and sprinkled generously with grated cheese, and pop the bowls under the oven grill for a few minutes until bubbly.

If you’ve made more soup than you can (or want) to eat over the next 3 to 4 days, pour the cooled soup into freezer-friendly, labeled containers (liter- or quart-sized is a good format), chill for a few hours in the fridge, then transfer to the freezer. (It’s ok to do that even if some of the ingredients you’ve used in the soup were previously frozen, as you’ve now re-cooked them.)

Join the conversation!

Do you make clean-out-the-fridge soup yourself? Any tips and tricks to add to the list? What other strategies to you adopt for produce on the decline?

  • Dylanthomasp

    My mother and grandmother used to make something called ‘Tail end of the Garden’, which was very similar but with meat. They would go out and pick everything that looked like it was ready or slightly beyond ready to use, bring it in, wash it, saute the meat with onion, salt and pepper, chop the veggies and start adding them to the meat with some water, potatoes and carrots first, then green beans, etc, up to tomatoes (which they did peel and quarter), then simmer on the stove until grandpa or daddy came home. I LOVED it and never realized until I left home that it was just a way to not waste anything. And I was amazed to find that French cooks do something similar!

    • I very rarely make soup with meat (even chicken soup!) but this sounds lovely. I’m not surprised you never realized then it was a waste-not-want-not strategy!

  • I absolutely love making soups like this. I always feel so sad when I realize I’ve let a fresh vegetable go bad in my fridge, and soups are the very best way to save from wasting. I also love adding bit of Dijon mustard! It’s such a great way to add a savory element if the soup tastes too sweet or bitter. If the produce looks especially poor, I like to make a vegetable broth out of it. Thanks for boiling down soup-making for us all!

    • I also hate (hate!) to see vegetables go limp on my watch, and although I vow to do better every time, I’ve learned it’s part of the process to a certain extent.

      • paul_cs

        I am the same way, and this has resulted in some pretty crazy meals. I’ve gotten better about making things and freezing them over the years, too. we’ve started freezing cut up summer squash, and it reheats well.

        • Good tip about freezing summer squash! I have also learned to be proactive and throw things into the freezer if I doubt I’ll be able to use them in time. Sometimes I end up using them the very next day, but better safe than limp. ;)

  • NotJoking

    I make something similar called “Richard’s Life-Saving Soup” which I came up with when my neighbour had a nasty bout of flu and couldn’t get warm. Loads of veg, especially tomatoes, some red lentils and lots of warm spices and herbs. Soon he could feel his toes again.

    • Love this story! If everyone had a neighbor as wonderful as you, I believe we would soon achieve world peace. :)

  • Annabel Smyth

    I make soup all the time! Lentils and carrots add the best mother, I find. I like to blend my soup in the blender, if I can be bothered (if not, I just use the stick blender) and then add a small tin of sweetcorn.

    • Annabel Smyth

      Mouthfeel, not mother! That’s what comes of being too eager to reply and using my tablet, rather than waiting until I had fired up my laptop! But I agree, clean-the-fridge soup is wonderful.

      • Jenny

        Hah, I was just thinking that ‘mother’ was one of those wonderful food idioms that Clotilde is always sharing.

        I’m sort of disappointed that it’s not because I think it would be wonderful one. The mother of the soup is the strongest or best element, sort of like we might say something is the backbone of it.

    • Do you find that the blender makes your soup smoother than the stick blender? I’ve been wondering.

      • Annabel Smyth

        Yes, I do – massively. It is a bore having to get it out, though, and if I have made the usual 2 litres of soup, you have to put the blended stuff into another container as you can’t do it all together, but it is worth it. If I’m going to be adding, say, pasta or beans to the finished soup I don’t bother so much, but if I want a smooth soup or to add a tin of sweetcorn, it is worth it (although the last soup I made was a minestrone, where I chopped or minced all the vegetables beforehand using the coarse grating disc and the chipper on my food processor).

        • Hm. That’s what I suspected, and it’s an inconvenient truth for sure. My countertop doesn’t need a new appliance! :)

          • Annabel Smyth

            Mine came as part of my food processor – perhaps an excuse for a new food processor, with its own blender, for Christmas? Mine also has a juicer, which is very useful at marmalade time!

          • Oh no, please don’t tempt me! :)

  • paul_cs

    I seem to always end up with leftover carrots, mushrooms, potatoes, and winter greens, so I keep a container of lentils du puy on hand, and make a lentil soup with all these things. It’s particularly tasty with lots of mushrooms, which I’ll brown well first. I’m usually a big fan of using homemade stock in soups, but I don’t find it necessary in this soup.

    another favorite “clean the pantry” soup is onion, sweet potato, winter squash, with some stock and a can of coconut milk.

    the indian soup sambhar is also an excellent vehicle for using summer squash and eggplant, I make this sometimes although. a lot of versions I’ve had in restaurants were quite thin broths of lentils, but the version I learned from Julie Sahni is thick and contains lots of vegetables.

  • I try so hard not to let vegetables go to waste, but I often fail. I make a ton of smoothies with greens, so that helps. But I love the idea of this soup for saving veggies and getting all your nutrition in :)

    Sues

    • Smoothies are a great idea! I hardly ever think of them as an option, so thank you for reminding me. What’s your favorite combo with greens?

  • I make a lot of soup, my mother was a Scot and we had soup every day, winter and summer. My favourite is lentil soup, an onion, 2 carrots, stick of celery and a cup of red lentils, fry everything gently in a little olive oil and then add two bay leaves and parsley stalks, sometimes, I add a slug of dry sherry or vermouth at this point and finely chopped parsley to decorate, I don’t always use stock for veg. soups, just water. I may liquidise it or add a bit of curry paste after the first day of eating it, or savoy cabbage which is slightly past its best is finely shredded and thrown in for a few minutes at the end. Left over tomatoes which have gone a bit soft make a great soup, roasted first and then mixed with Asian spices and coconut milk. Served with a little basil oil on top.

    • This sounds truly wonderful. What sort of curry paste to you add in?

      • I am pleased that you like the sound of my lentil soup, for me, it’s la mémoire du temps perdu. I keep a jar of Patak’s Madras Curry Paste handy and use a teaspoonful in soups such apple & parsnip, lentil and of course for kedgeree. Here in France, I have seen different brands, but never tried them.

        • I believe I’ve seen that brand at the specialty grocery stores — I’ll double-check and give it a try, thanks!

  • Jake

    I do this a lot, not as much as I should. Adding the rind of a hard cheese is also good. I’ve aslo added leftover stale bread.

    • Ah yes, I wanted to mention the cheese rind as a flavor booster too! I like it but Maxence not so much, so I usually resort to other tricks. :)

  • This came just when I needed it!

  • Jenny

    My favorite is to use winter veggies and roast them first. I usually use potatoes, sweet potatoes, butternut or other winter squash, maybe parsnips, and a bit of onion. I guess mine is more of clean out the cupboard than fridge.

    I chop them all and roast them with oil and salt until they are almost burned or slightly charred in places, then boil them all in chicken broth until they are tender then puree them with my immersion blender. I like to add a bit of curry powder and some cinnamon for flavor, and maybe melt a little butter on top or add a splash of cream to each bowl.

    • I love a roasted vegetable soup too, and your method sounds wonderful. But I am so short on time these days that the prospect of the double-cooking (and extra baking sheets to wash) keeps me from making the soup at all, so I stick to the quick boiling-only method.

  • Great post! I love the chicken juice tip! I like to add rehydrated dried mushrooms and their soaking water for flavour. My favourite garnishes are chopped crispy bacon or sliced chorizo.

    • Dried mushrooms are a great idea! Is it actually necessary to soak them first, or could them just be added in dry to rehydrate while the soup cooks?

      • I prefer pre-soaking so that I can filter out any dirt from the soaking water before adding to the soup.

  • Shivangni

    What a thoughtful post, absolutely loved it. I somehow had the notion that Europeans don’t fry soup vegies, perhaps that’s the reason our soups tend to be quite bland and are not really popular.
    My hubby loves obliging the farmers & going off on tours,so am usually saddled with lot of limp vegies.
    So, today the family will be served glamored up version of over dated vegetables in the form of soup tonight!

    • I hope it turns out great, Shivangni, do report back if you get a chance!

  • This is exactly what I needed this weekend! Thanks so much!! I think I’m going to be using this “recipe” often.

  • i like to eat vegetable soup. it will help full to me. thanks for upload.

  • Athene

    My kind of favorite recipe. My father used to joke that I almost never cook anything the same more than once. I just love the magic of figuring out how each ingredient will react and work with another one, no matter how incompatible they may seem.

    One of my most loved childhood comfort food is this Indian style lentil mush that they add whole eggs to at the end of the cooking and topped with onion, panch phoron spice mix and curry leaves that’s been tempered in some oil. Everyone else eat it with rice and a side of dried fish as they usually do here in Asia, but of course I must eat it like a soup and finish half of the pot before anyone else had the chance to have any.

    • That sounds wonderful Athene! I’m not going to ask for a recipe, but I wish you could provide one. :)

  • manillesol

    Clotilde, I clicked through to this soup after finding your post on kale chips which are in the dehydrator as I speak! I wanted to find a use for the stems, but I am hesitant my experience with kale stems, especially curly kale, is that they are incredibly fibrous. I can’t imagine them being edible, even after 7 mins in my Vitamix… what was your experience with them?

    • I slice them thinly and add them to stir fries and such!

      • manillesol

        Thanks! And they were fine in the soup? Not too stringy?

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