Leek and Potato Soup

This cream of leek and potato soup recipe is simple, stylish, easy to make and more full of flavour than you would ever imagine you could achieve with such simple ingredients.

Leek and potato soup

Cream of leek and potato soup is a subtle and delicious blended soup made with the simplest, most frugal of vegetables and enriched with cream. My version is rustic, a little more robust than the haute cuisine version known as vichyssoise, but delicious nonetheless.

See also

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The complexity of the flavour of this wonderful soup belies the simplicity of the ingredients. It is simply delicious, warming and full of flavour.

That complexity comes from allowing leeks and potatoes to really shine through. These two vegetables are often stuck in supporting roles and even used as ballast, so that the flavours are neglected and overwhelmed by more assertive ingredients.

Not so here. This leek and potato soup recipe makes the most of these winter heroes. It’s easy to make yet deliciously impressive, so why wait? Let the most frugal veg on the vegetable rack have their moment in the spotlight with this irresistible soup.

What is Vichyssoise?

Vichyssoise is a variation on the classic, simple leek and potato soup or potage parmentier, a French staple.

The French chef Louis Diat, who went from head soup maker at the Ritz Hotel in Paris, to the London Ritz and then the Ritz-Carlton in New York, is credited with inventing vichyssoise during his time as head chef at the Ritz-Carlton in the early years of the 20th century.

He added milk and cream to the traditional leek and potato soup, remembering that his mother had done so to cool the soup for her children. He then strained it to a smoother purée than usual, added chopped chives as a garnish, and named his soup after his home region of France, near Vichy.

Vichyssoise can be served hot, warm or chilled, and often appeared on Diat’s menus as crème vichyssoise glacée. In fine dining establishments, it is often made with only the white parts of the leek for a soup that is almost white.

Why make leek and potato soup?

• easy to make

• fabulous flavour

• affordable luxury

Leek and potato soup ingredients

• Leeks – choose leeks that are largely white and clean. The most refined versions of this recipe demand only the whitest part of the leek, but I don’t mind a little green in my leek and potato soup. I only worry about this for a fancy dinner party.

• Potatoes – I personally do not think that the type matters too much here. Potato is an important part of the recipe but it is not the main ingredient by weight / volume.
  Use whatever is in the vegetable rack. As long as the skins are in good condition, you can leave them on, but if you are aiming for something closer to a classic vichyssoise, you will want to peel them.

• Onion – one white/yellow onion, you could also use a couple of shallots.

• Butter – can be salted or unsalted, but take this into account when seasoning

• Oil – I almost always sauté vegetables in mix of butter and olive oil. You do not want your best strongly flavoured oil for salad dressings here. Any unrefined olive oil will do. You will be lightly sautéing so there are no worries about smoke point and as long as it is not too strongly flavoured you cannot taste it.

• Stock – vegetable or chicken stock, as you prefer

• Bay leaves – a classic, subtle addition to many French recipes

• Milk – If you have whole milk you can use a little less cream and if you are using skimmed milk you may want a little more cream. It all balances out, so use what you have.

• Cream – I used double. If you only have single, then use that, double the quantity and leave out the milk. For a richer soup use all cream.

How to make leek and potato soup – step by step

Before you start, read my step-by-step instructions, with photos, hints and tips so you can make this perfectly every time.

Scroll down for the recipe card with quantities and more tips at the bottom of the page.

Step One – Prepare the vegetables. You don’t need to worry about how they look, as this is a blended soup, but cutting similar sized pieces ensures even cooking.

• Leeks – trim any tough leaves, cut in half lengthwise and then slice. If dirty, rinse well and spin in the salad spinner or pat dry. This will look like a lot of leeks, but they cook down.
• Potatoes – cut into cubes of about 2 cm / just over ½“ so that they cook quickly. If the skins are in good condition, leave them on.
• Onion – peel and chop

Helen’s Fuss Free Tip

The vegetables need to be dry so that they sauté rather than steam, so if you need to wash your leeks do dry them.

Step Two – In the soup pan, gently melt the butter into the oil and sweat the leek and onion until meltingly soft and reduced by about a third in volume (about 7–12 minutes).

Step Three – Add the potato, stock and bay leaves. Cover with the lid and simmer until the potatoes are soft (about 10 minutes).

Step Four – Remove the bay leaves. If you like, you can also remove and reserve some of the vegetables to garnish the blended soup and give a variety of texture.

Then remove from the heat and blend the soup to a smooth purée. I like to do this with a stick/immersion blender in the pan.

Helen’s Fuss Free Tip

A cheap stick/immersion blender is the simplest and best way to blend soup. I have had mine for years.

If you must use a jug blender with hot soup, never use the central bung. As you blend, it will generate steam which can blow the lid off and send scalding soup everywhere. 

Instead, cover with a folded piece of kitchen paper, then a tea towel over the top. Lift from time to time between each blend to allow the steam to escape.

Step Five – Now stir in the cream and milk, mixing them in thoroughly. Check you are happy with the consistency.

You can thin the soup with a little extra stock if you prefer. Season well with black pepper and salt if needed, garnish to taste and serve.

Serving suggestion

Serve hot or chilled.

I like to garnish this soup with some reserved leek and potato, a swirl of cream or a few drops of olive oil, and a scattering of chopped chives.

Variations

• For a paler soup, use only the white parts of the leeks and peel the potatoes. This looks stylish for entertaining, making a stronger contrast with the chives.

• You can add other herbs such as thyme or oregano, but remove the stalks when you remove the bay leaves.

• For a skinny version, use semi skimmed milk instead of milk and cream.

• Add a chopped stick of celery or some fennel with the leeks or a chopped apple with the potato to vary the flavour a little. I don’t think this soup needs garlic, but if you wanted, you could add that to the frying leeks about halfway through.

• If you have leftover boiled or mashed potato to use up, you can reduce the quantity of raw potato and add this before blending.

• Add just a touch of curry powder.

Storage

This leek and potato soup recipe will serve four as a meal with some hearty bread, or six as a starter, so if you are making it for one or two, you will have a second serving for tomorrow or to freeze for later.

Fridge – Once cool, cover and store in the fridge, where it will keep for up to three days. Reheat in a pan on the stove or in the microwave.

Freezer – Transfer the cooled soup to airtight containers and freeze your leek and potato soup for up to three months. See notes on adding milk and cream in hints and tips below.

Reheating – Defrost your soup in the fridge overnight, or on the kitchen counter for a few hours. Reheat in a pan on the stove top, or in a safe container in the microwave. When using the microwave, I like to use a Pyrex-style jug as you can lift it out one handed and pour it out easily.

Hints and tips

• If you are making a bigger batch to freeze, hold the milk and cream back, adding it when you have reheated the soup. This removes any risk that your soup may curdle if reheated too aggressively, and your soup will take up less space in the freezer!

• This recipe is flexible and you can vary the proportions, but don’t get carried away adding too much extra potato. A bit of extra potato can give a thicker soup or bulk out the recipe but if you go too far, this can result in a rather gummy texture, which will be disappointing.

• If you use a jug blender, don’t use the bung!

FAQs

More leek recipes

• French chicken casserole – perfectly simple and delicious

• Leek rice – a deliciously simple pilaf that goes with everything