With bunches of fresh watercress, there's nothing better than this healthy French classic, watercress soup. Naturally vibrant green, it's packed with vitamins with a gorgeous spicy flavour. Personally, I find it a bit cheesy without the cheese.
I made your watercress soup. Absolutely delicious!
Watercress is very nutritious. Your recipe made it enjoyable for all at our table. Thank you. - Susan
The French Love for Cresson and Watercress Soup
In France, it's popular in Autumn and Winter at the market to see stacks piled high of neatly tied bouquets or bundles of watercress.
Each time I discuss watercress (cresson) with the market sellers, there's really only one recipe the French associate with it - and it's watercress soup! Approved by my French family - and a family favourite of my Corsican Parents-in-Law - it was one of Princess Diana's favourite soups.
In April, enjoy the French watercress festival, Fête du Cresson in Veules-les-Roses. For more on Normandy, read my top 10 reasons to visit Honfleur.
Is Watercress Soup Good for You?
A comforting bowl of watercress soup is extremely healthy, nutritious soup as it contains vitamins and minerals such as iron, calcium, potassium, vitamin C, K and it's a good source of protein and antioxidants. It's even said to reduce the effects of skin ageing.
For its health benefits, how it's grown and more recipes,
see the Market Guide to Watercress.
How do you Make Watercress Soup Not Bitter?
Watercress is known for its fine, soft leaves and particularly spicy, bitter taste when raw. However, this bitterness subsides when cooked so there's no need to even add any sugar or sweet vegetables.
Once cooked in soup with a large floury potato and a little nutmeg, it even has a slight taste of cheese to it. Don't ask why but my daughters confirm they get that too!
It's so naturally vibrant green that there's no need to add any other green vegetable to it. That way you have it pure and simple: the taste is fabulous.
For more on pommes de terre and other potato varieties for cooking,
see French Potatoes.
Watercress Soup Ingredients
To get the best out of your watercress, I recommend not overloading on the ingredients. Keep it simple to appreciate its natural flavour. For this recipe, it's so good, I often double the quantities.
- Fresh watercress - choose the greenest as possible and try to make the soup if possible within 2 days of buying it.
- Potatoes - floury varieties are best for soup, such as Binje in France or King Edward, Maris Piper, Cosmos and Desiree. Use one large or 2 medium.
- Onion and garlic - one of each, finely chopped.
- Ground nutmeg - please don't make it without nutmeg. It's the secret ingredient that works.
- Vegetable stock - or use chicken.
- Butter and olive oil - I use a mixture of both.
How to Make French Watercress Soup
First prepare the watercress. Chop off the bottom stalks where the bundle is tied and wash the leaves. If they're particularly gritty, wash in a bowl of water with a few drops of vinegar or in a sink of cold salted water.
Discard only the large, thick stalks (long parts) and keep the thin ones with the little leaves on them. Keep a few little leaves aside for the garnish.
Chop a small onion, a garlic clove and potato.
In a large saucepan, heat the butter and olive oil until melted (not browned). Sweat the chopped onion and garlic for about 5 minutes until translucent and add the ground or grated nutmeg.
Over a medium heat, add the chopped potato, watercress and cover with the vegetable stock (or chicken if you prefer). Heat on high at first, then reduce heat to a simmer and cover with the lid slightly askew to let a little steam escape.
Cook gently for about 20 minutes or until the potato(es) soft.
Blitz the soup with a stick blender then add sea salt and pepper to your personal preference (use French fleur de sel, otherwise UK Maldon salt or US Celtic salt).
How Long Does it Keep?
Soupe au cresson lasts in the fridge well covered for up to 3 days. Just cool it first before storing in the refrigerator.
Watercress soup freezes well. Leave the soup to cool and chill in the fridge in large jam jars or sealed bags then transfer to the freezer. Use within 3 months.
What to Serve with Watercress Soup
French watercress soup goes well with light accompaniments, so not to interfere too much with its subtle flavours. Top with the little watercress leaves, stir or swirl a dash of cream or a wee dollop of crème fraîche. It's excellent paired with cheesy bread plus:
- A crusty baguette with either a little butter or dip into good olive oil.
- Leftover rice: like this carrot soup, add some rice if you prefer without potato.
- Surprise your guests with a mini savoury herb macaron
- Serve with fluffy cheese scones.
- Serve as mini soups as an apéritif with cheese biscuits or Parmesan crisps.
- Leftover soup? Use the rest of the soup to make a lush sauce, using the basis of this beurre blanc. Just replace the lemon with 3-4 tablespoons of watercress soup and pour over baked salmon, pork ribs or roast chicken.
Watercress Soup (Soupe au Cresson)
Equipment
Ingredients
- 25 g (1oz/ ¼ stick) butter
- 1 tablespoon olive oil
- 1 small onion finely chopped
- 1 clove garlic finely chopped
- ¼ teaspoon ground nutmeg
- 1 large floury potato (Binje, Maris Piper) peeled, roughly chopped
- 750 ml (3 cups) vegetable stock (or chicken broth)
- 1 large bunch of watercress 200g once prepared - smaller stems included (big woody ones discarded)
- 1 teaspoon sea salt & black pepper to taste
Instructions
- Wash the watercress, drain in a colander and set aside. Chop off the bottom stalks and keep the smaller stems (discard the large, thick stalks) and reserve a few smaller leaves for the garnish.
- Heat the butter and olive oil in a large saucepan or heavy pot. Sweat the onion and garlic until cooked but not browned for about 5 minutes.
- Add the nutmeg then the chopped potato, watercress leaves (including the smaller stems) and stock. Heat to only a brief boil (the leaves will quickly wilt) then lower the heat and simmer, covered with the lid slightly askew to let some steam escape. Simmer gently for up to 20 minutes on low heat until the potato is cooked through.
- Blitz the soup with an immersion blender or in a food processor until smooth. Season with salt and black pepper to your taste and top with the remaining watercress leaves.
Notes
This post was first published 5 November 2013 but has now been completely updated.
Jayne Jackson
I'm a little unsure of your quantities of stock? I've put 1.5 pints (as per recipe) and the soup seems very watery. I note you've used 3 cups as an alternative measure....perhaps my measuring cup set isn't accurate but 3 cups add up to just a teensy bit over 1pint. If I had used the cup as a measure I'm sure the recipe would be better. Look forward to hearing your comments.
Jill Colonna
Hi Jayne, thank you for flagging this - you’re right, the pint measurement has caused confusion here as UK and US pints differ. I’ve now removed pints from the recipe and kept it in ml and cups for clarity.
If your soup turned out watery, it can also be due to the potato quantity, as this is what naturally thickens it - do make sure that’s included.
Thanks again for pointing this out, and I hope you’ll give it another go.