How to make the perfect chilled cucumber soup – recipe

On the first really warm day of the year, I went out and bought a carton of gazpacho from sunnier climes – when it’s so hot that your trainers stick to the tarmac, even I tend to lose my appetite for anything apart from cold liquids. And there’s nothing more refreshing than cucumber, a vegetable that’s 96% water and 100% delicious, green coolness. Many cultures around the world have a cucumber soup recipe in their repertoire – Iranian abdoogh khiar, Indian kheere ka shorba and Polish chłodnik ogórkowy, to name a few – and here’s mine.

The cucumber

It’s time to focus on cucumber, so often simply chopped up and tossed in as a last-minute addition to a salad, as more than just a crunchy bit on the side. Most soup recipes call for it to be peeled before use (and if you’re planning to serve it in elegant little cups, then this may be the way to go), but I like the faintly bitter flavour of the paper-thin coating on your average British cucumber, so I’m going to keep it on. I would, however, remove the seeds, because they taste of very little and risk leaving your soup rather watery. (Note, if the cucumbers you have are stouter of skin, peel them; it’s the work of a minute, after all.)

Chef Anthony Demetre cautions readers of his book Today’s Special to avoid the temptation to skip “the salting and degorging process: cucumber juices may be less bitter than they once were, but they are still fairly indigestible”. Both he and Simon Hopkinson sprinkle the chopped pieces with salt and leave this to draw out the juices from the flesh, which leads me down an interesting rabbit hole that ends in the discovery that “burpless cucumbers” (as Jane Grigson notes, they are “coyly known”) are a relatively recent phenomenon in the very long history of cucumber appreciation. They now seem to be almost the only show in town in the UK (unless, chef and food writer Thom Eagle informs me, you get lucky with heritage varieties), and salting them risks making the finished product rather salty for some palates, so I’m going to skip this step – but, again, if you’re using homegrown or otherwise more windy fruits, as Grigson also charmingly terms them, you may wish to do so. Simply scatter them with a very little salt and then leave in a colander for half an hour or so before continuing with the recipe.

Chef Tom Kerridge lightly sautes the cucumber, which makes his recipe a halfway house between the raw versions of Demetre, Hopkinson and others and the cooked sort featured in Margaret Costa’s Four Seasons Cookery Book and Clarissa Dickson Wright’s Comfort Food, which seem to link back to the hot cucumber soups of Eliza Acton and her Victorian ilk. Although I can’t detect any real difference in taste, save for the fact that the cucumbers take on the flavour of the oil or butter they’ve been cooked in, and that the softened cucumbers are certainly easier to puree, I’m loth to recommend turning on the stove unnecessarily in high summer, not least because it means the soup will take longer to chill to serving temperature.

The liquid

Of course, removing the seeds because they’re too watery may strike some as counterintuitive, given that the soup needs diluting with something, and indeed Kerridge includes sparkling water in the version in his book Best Ever Dishes, explaining it helps make the dish “really light and airy”. Like the other recipes I try, however, he also adds dairy, a classic pairing with cucumber, in the form of Greek yoghurt. It’s also the choice of the mysterious “Tom”, whose recipe was published in the New York Times in 1973, and who combines it with soured cream. Demetre uses milk and creme fraiche, Jonathan Meades calls for iced water and caillé, which he describes in the Plagiarist in the Kitchen as “fermented and very light, of Basque origin, at the far end of the spectrum from Greek yoghurt”, though he concedes sheep or goat yoghurt may be substituted. Henrietta Clancy uses natural yoghurt in her book Just Soup, and Paul Gayler Greek yoghurt, along with the water disgorged from the cucumbers, in his collection of Great Homemade Soups.

Hopkinson, whose soup does indeed have the “most fragrant combination of flavours”, mixes yoghurt and single cream with chicken stock (from a cube, for preference) and tomato juice, Dickson Wright goes for single cream and chicken stock, thickened with a roux, and Costa chicken stock and cream thickened by both flour and egg yolk. Delicious as Costa’s soup is, it tastes more like a rich, chilled chicken soup than anything fresh from the garden, while Hopkinson’s has a distinctly sophisticated complexity that, while a pleasure to eat, doesn’t scream cucumber to my panel of testers. We all prefer the simpler cucumber and dairy soups, deciding that the ideal combination for refreshment is the lightness of yoghurt (I like Meades’ goat variety) with the tanginess of something such as creme fraiche or soured cream. If you’d like an even lighter result, you could replace the creme fraiche with enough cold water to achieve a pourable consistency, though if you do so, I’d suggest serving it in smaller portions.

Flavourings

As with so many recipes, alliums deserve a look-in here, but not in the form of Kerridge’s onion or Costa’s shallots, both of which require cooking, but garlic, which can simply be grated or chopped and stirred in. Feel free to put in more than in the recipe below if you’d like a tzatziki kind of vibe, but remember that a little garlic can easily overpower a lot of cucumber. Kerridge also adds a mild green chilli, which I consider a stroke of pure genius: though it contributes little in the way of heat, especially given the cooling effects of both dairy and cucumber, its herbaceous greenness works brilliantly to enhance similar flavours in the cucumber itself.

Herbs are also popular, particularly mint, chives or dill. I’ve gone for dill, because it reminds me happily of pickled cucumbers, but if, like many, you’re not a fan of its anise flavour, swap in your own favourite soft herb instead. The tang of the yoghurt means there should be no need for the spritz of citrus in Kerridge, Costa and Dickson Wright’s recipes, but taste it and see – brands, as well as tastebuds, differ.

The garnish

Though I’ve lazily stuck with just diced cucumber and chopped herbs, it’s easy to make this soup into a more substantial dish by topping it with curls of smoked salmon, as Demetre recommends, cooked prawns, as in Hopkinson’s recipe (an excellent pairing with sweet, juicy little North Sea numbers), or chopped walnuts, to keep it vegetarian. To spice it up, you could finish the soup with a pinch of cayenne pepper or more chopped chilli, or, of course, you could serve with “a big splash of frozen vodka, if you want to live life to the full”. Well, if it’s good enough for Tom Kerridge …

Perfect cucumber soup

Prep 10 min
Cook n/a
Serves 4

2½ large cucumbers
1 small garlic clove, peeled and crushed
1 mild green chilli, trimmed, deseeded and roughly chopped
300ml whole milk plain yoghurt (I like goat’s)
100ml full-fat creme fraiche, or soured cream
1 small bunch dill, mint or chives
Salt

Cut the cucumbers in half lengthways …

… then scoop out and discard the watery seeds.

Roughly chop two of the cucumbers and put them in a blender with the garlic and chilli.

Add the yoghurt and creme fraiche or soured cream, and blitz until fairly smooth.

Roughly chop the leaves of your chosen herb, and add most, but not all of them to the blender, along with a good pinch of salt. Whiz again, then taste and adjust the seasoning as necessary.

If you have the time, now chill the soup.

Meanwhile, cut the remaining cucumber into fine dice. Divide the soup between bowls, sprinkle with the cucumber pieces and remaining herbs, and serve.

• UK readers: click to buy these ingredients from Ocado

• Chilled soups: the best way to cool down on a hot day, or distinctly inferior to an ice lolly? Apart from obvious contenders, such as gazpacho, which are your favourite recipes?
  

• Felicity Cloake’s new book, Red Sauce Brown Sauce: A British Breakfast Odyssey, is published by HarperCollins at £16.99. To order a copy for £14.78, go to guardianbookshop.com