Mary Berry Mushroom and Leek Soup

This soup started as a bit of a fridge-clearer on a cold Tuesday, if I’m honest. I had half a pack of mushrooms going soft, a few leeks looking sorry for themselves, and one lonely potato left in the drawer. I figured: throw it all in a pot and hope for the best.

The first version was… fine. Not bad, just flat. The mushrooms got a bit lost, and the whole thing tasted more beige than bold. But after a few tweaks (and accidentally discovering that tarragon absolutely sings in this), it turned into one of those comforting, silky soups I now batch-make and stash in the freezer.

If your soup often ends up bland or watery, let me show you how I fixed that.

Why This One Works So Well

The leeks and mushrooms play off each other brilliantly—but it’s the potato that gives this soup real body. No cream soup that tastes like water here. The starch from the spuds thickens everything naturally, so you get that luxurious texture without needing loads of dairy.

Also? Tarragon. I know, I didn’t expect it either. But it lifts the whole thing—like a squeeze of lemon but more mysterious.

Most recipes skip browning the veg, but don’t. That 5 minutes of frying adds proper depth. I’ve made the lazy version and the rich version—and trust me, it’s worth the sizzle.

INGREDIENTS + WHY THEY MATTER

• Sunflower Oil + Butter – The combo gives a light base with buttery flavour. Just oil is too flat; just butter burns.
• Leeks – Sweet, mellow, and softer than onions. Must be well cleaned—those layers hide dirt like you wouldn’t believe.
• White Mushrooms – Cheap, cheerful, and perfect here. Chestnut mushrooms work too, but they make the soup darker and a bit more savoury.
• Potatoes – For creaminess without cream. I used floury ones (like Maris Piper) and they broke down beautifully.
• Stock (Veg or Chicken) – Use what you have, but homemade or low-salt stock makes a big difference.
• Double Cream – Just a swirl for richness. Skip it if you’re dairy-free—the soup still works.
• Tarragon – Earthy, slightly aniseed-y, and the secret hero of this soup. Don’t overdo it though.

Making It Yours (Without Ruining It

• Dairy-Free? Leave out the butter and cream. Use olive oil and a splash of oat milk at the end—it stays smooth.
• No Tarragon? Try fresh parsley or thyme. Just don’t use dried tarragon—it’s too sharp.
• Chunky Version? Blend half the soup and stir the rest back in for texture.
• Mushroom Upgrade: Swap in some wild mushrooms for a fancier twist. I did it once with girolles—divine, but pricey.

MISTAKES I’VE MADE (AND HOW TO AVOID THEM)

What Went Wrong	Why It Happens	How to Fix It
Soup tasted bland	Didn’t brown the leeks/mushrooms	Give them 5–7 mins on high heat to caramelise
Mushrooms turned slimy	Overcrowded the pan	Cook in batches or use a wide saucepan
Texture was watery	Used waxy potatoes (like Charlotte)	Use floury ones like Maris Piper or King Edward
Flavour disappeared after freezing	Too much water, not enough seasoning	Reduce slightly before freezing + season well

HOW TO MAKE MARY BERRY’S MUSHROOM AND LEEK SOUP

1. Heat the base: In a large saucepan, heat 1 tbsp sunflower oil and a knob of butter over medium-high heat.
2. Sauté the veg: Add 3 sliced leeks and 350g chopped mushrooms. Fry for 5–7 minutes, stirring often, until soft and golden. Don’t skip this—it builds flavour.
3. Add potato and stock: Stir in 2 diced potatoes and pour over 750ml hot stock. Season with salt and pepper.
4. Simmer: Bring to the boil, then reduce heat. Cover and simmer for 15 minutes until potatoes are soft.
5. Blend: Let it cool a bit, then blend until smooth. I use a stick blender right in the pan.
6. Finish: Stir in 4 tbsp double cream and 1–2 tbsp finely chopped tarragon. Taste and tweak the seasoning.
7. Serve: Ladle into bowls with an extra swirl of cream and a bit more tarragon if you fancy.

TIPS FROM MY KITCHEN

• I chop the mushrooms roughly so they brown faster—don’t crowd the pan.
• I blend the soup just before serving, not hours ahead—it keeps it fresher.
• If I’m freezing it, I leave the cream out and stir it in after reheating.
• I always taste before serving—mushroom soups need more salt than you think.

STORAGE + SERVIN

• Fridge: Keeps well for 2 days. Reheat gently with a splash of water or stock.
• Freezer: Freeze without cream for up to 3 months. Thaw overnight, then reheat and swirl in cream.
• Pair it with: Warm crusty bread or cheese toasties. It’s light enough for lunch, rich enough for dinner.

FAQs

Q: Can I use chestnut mushrooms instead of white?
A: Absolutely—they give a deeper flavour and a browner colour. Great swap.

Q: Can I leave out the potatoes?
A: You can, but the soup will be much thinner. Add a splash of cream or blend in a tin of cannellini beans if you still want that creamy texture.

Q: How do I stop mushroom soup tasting “muddy”?
A: Don’t overcrowd the pan, brown the veg properly, and season generously. Also, fresh herbs (like tarragon or parsley) lift the flavour massively.

Q: Can I make this in advance for guests?
A: Yes! Just hold back the cream and herbs until reheating. It tastes even better the next day.

Q: What’s the best way to blend it smooth?
A: A stick blender works best. If you use a jug blender, cool the soup first and blend in batches to avoid explosions (trust me).

Try More Mary Berry Recipes:

• Mary Berry Chestnut Mushroom Soup
• Mary Berry Tomato and Basil Soup
• Mary Berry Chicken Noodle Soup
• Mary Berry Vegetable Soup