Anna Louise There are soups that require a long list of ingredients and complicated technique, and there are soups that ask almost nothing of you and give back everything. Leek and potato soup is firmly in the second category — and it is all the better for it.
Four main ingredients. One pot. Forty minutes. The result is a soup that is silky, deeply comforting, and far more flavourful than its simplicity has any right to produce. The leeks give a mild, sweet onion flavour that is unlike any other vegetable.
The potatoes thicken and enrich. A good stock ties everything together. And blending — either partially or fully — transforms what starts as a humble collection of chopped vegetables into something smooth, elegant, and completely satisfying.
Mary Berry’s leek and potato soup is the version I make more than any other soup on this site. It works as a weekday lunch, as a dinner party starter, as something warming to come home to on a cold afternoon.
It is endlessly versatile, completely reliable, and one of the finest things British home cooking produces from such simple ingredients.
What Makes This Leek and Potato Soup So Good?
Sweating the leeks slowly. The leeks need time — at least ten minutes over a gentle heat — to soften completely and develop their natural sweetness. Rushing this stage gives you a soup that tastes raw and sharp rather than sweet and mellow.
Using floury potatoes. Floury varieties such as Maris Piper or King Edward break down during cooking and give the soup its characteristic silky, slightly thick body. Waxy potatoes remain too firm and the blended soup will be less smooth and slightly starchy.
A good quality stock. With so few ingredients, the stock is the backbone of this soup. A good homemade chicken or vegetable stock makes a noticeable difference — but a good quality shop-bought fresh stock works perfectly well.
Ingredients for Mary Berry Leek and Potato Soup
- 50g unsalted butter
- 1 tbsp olive oil
- 4 large leeks, trimmed, washed thoroughly, and sliced into rounds
- 1 large onion, roughly chopped
- 2 garlic cloves, crushed
- 750g floury potatoes (Maris Piper or King Edward), peeled and cut into roughly 2cm cubes
- 1.2 litres good quality chicken or vegetable stock
- 150ml double cream (plus extra to serve)
- Salt and freshly ground black pepper
- Freshly grated nutmeg
To Serve
- A swirl of double cream or crème fraîche
- Fresh chives, finely snipped
- Crusty bread or warm rolls
How to Make Mary Berry Leek and Potato Soup — Step by Step
Step 1 — Sweat the Leeks and Onion
Melt the butter with the olive oil in a large, heavy-based saucepan over a low to medium heat. Add the sliced leeks and chopped onion and season with a little salt and pepper.
Cook gently, stirring occasionally, for 12 to 15 minutes until completely softened and sweet-smelling — the leeks should be very tender but not coloured. This slow sweating is the most important step in building the flavour of this soup. Do not rush it and do not allow the leeks to brown — you want them sweet and yielding, not caramelised.
Add the garlic and cook for a further two minutes.
Step 2 — Add the Potatoes and Stock
Add the potato cubes to the pan and stir to combine with the leeks. Pour in the stock and bring to the boil over a medium-high heat.
Once boiling, reduce the heat to a gentle simmer, cover, and cook for 20 to 25 minutes until the potatoes are completely tender — a knife should slide through them with no resistance at all.
Step 3 — Blend
Remove the pan from the heat. Using a stick blender, blend the soup until completely smooth and silky. If you prefer a slightly more textured soup — a classic vichyssoise style — remove a ladleful of the cooked leeks and potatoes before blending, blend the rest until smooth, then stir the reserved chunks back in.
If using a standard blender, work in batches and be very careful with the hot liquid — fill the blender no more than halfway, hold the lid down firmly with a folded tea towel, and start on a low speed.
Step 4 — Finish With Cream and Season
Return the blended soup to the pan over a low heat. Stir in the double cream and warm through gently — do not let it boil after the cream has been added. Grate in a little nutmeg and taste for seasoning, adjusting salt and pepper as needed. The soup should taste rich, sweet, and deeply flavoured.
Step 5 — Serve
Ladle into warm bowls. Add a swirl of double cream or crème fraîche, a scattering of freshly snipped chives, and a twist of black pepper. Serve immediately with crusty bread.
My Top Tips for the Best Leek and Potato Soup
Wash the leeks thoroughly. Leeks trap soil and grit between their layers as they grow, and inadequate washing means gritty soup. Slice them first, then place in a large bowl of cold water, swish vigorously, and lift out with your hands — the grit falls to the bottom of the bowl. Repeat if the water is particularly dirty.
Sweat the leeks slowly — do not brown them. Twelve to fifteen minutes over a low heat is the right approach. Browned leeks give a different, slightly bitter flavour that is at odds with the delicate sweetness of a great leek and potato soup. Low and slow, until completely yielding.
Use floury potatoes. This is not interchangeable with waxy potatoes. Floury varieties — Maris Piper, King Edward, Desiree — break down during cooking and give the soup its characteristic silky body. Waxy potatoes give a starchy, slightly gluey result when blended.
Blend thoroughly for a silky finish. A stick blender gives a very smooth result but a standard blender gives an even silkier one — the more powerful motor breaks down the starch more completely. If using a standard blender, pass the blended soup through a fine sieve for the silkiest possible finish.
Season in stages. Add a little salt when the leeks go in, taste again after the potatoes have cooked, and taste a final time after adding the cream. The cream adds richness but also slightly mutes the seasoning — a final adjustment at the end always brings everything into focus.
Warm the bowls before serving. This takes 30 seconds and makes a real difference — soup poured into a cold bowl begins to lose temperature immediately. Simply fill each bowl with just-boiled water, leave for a minute, then pour out and fill with soup.
Serving Suggestions
As a lunch with crusty bread and good butter — the most satisfying combination. As a starter before a light main course — a small, elegant portion with a swirl of cream and chives.
As a simple supper in a large mug on the sofa when the weather is at its worst. All are equally valid and equally wonderful.
How to Store Mary Berry Leek and Potato Soup
In the fridge: Store in an airtight container for up to 3 days. Reheat gently on the hob, stirring occasionally, until piping hot. Add a splash of stock or milk if it has thickened too much in the fridge.
In the freezer: This soup freezes beautifully for up to 3 months — freeze before adding the cream for the best texture. Defrost overnight in the fridge and reheat gently, stirring in the cream once warm.
Mary Berry Leek and Potato Soup
Ingredients
Method
- Melt butter with olive oil in a large pan over low-medium heat. Add leeks and onion with a little salt and pepper. Cook gently for 12–15 minutes until completely softened and sweet — do not brown. Add garlic, cook 2 minutes.
- Add potato cubes and stock. Bring to the boil, then reduce to a gentle simmer. Cover and cook for 20–25 minutes until potatoes are completely tender.
- Remove from heat. Blend until completely smooth with a stick blender, or in batches in a standard blender.
- Return to low heat. Stir in double cream and warm through gently — do not boil. Grate in a little nutmeg. Taste and adjust seasoning.
- Ladle into warm bowls. Swirl over cream or crème fraîche, scatter chives, add a twist of black pepper. Serve with crusty bread.
Notes
Frequently Asked Questions About Mary Berry Leek and Potato Soup
Can I make this soup without cream?
Yes — the soup is delicious without cream and significantly lighter. Simply omit it, or replace with a spoonful of crème fraîche stirred into each bowl when serving, which gives a pleasant tang alongside the richness of the soup.
Can I make leek and potato soup vegan?
Yes — use olive oil instead of butter, vegetable stock instead of chicken stock, and omit the cream or replace with a plant-based cream alternative such as oat cream. The flavour is still excellent.
Can I serve this soup cold?
Yes — cold leek and potato soup is the classic French dish vichyssoise. Make the soup as directed, chill thoroughly in the fridge, and serve cold in chilled bowls with a swirl of cream and chives. It is refreshing and elegant as a summer starter.
Why is my soup not silky? Usually because waxy potatoes were used rather than floury ones, or the blending was not thorough enough. Use Maris Piper or King Edward, blend for at least two full minutes with a stick blender, and pass through a sieve if you want the absolute silkiest result.
Can I add cheese to leek and potato soup?
Yes — a handful of mature Cheddar or a little Gruyère stirred into the hot blended soup adds a wonderful richness and a slightly more complex flavour. Stir in after adding the cream and heat gently until melted.
How do I stop the soup sticking to the bottom of the pan when reheating?
Reheat gently over a low heat, stirring frequently, and add a splash of stock or water if the soup has thickened considerably in the fridge. A thick potato-based soup will catch and burn on a high heat very quickly — always low and slow when reheating.
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