Wondering what to make with celeriac? Make Celeriac Soup! Beautifully creamy with an elegant, near pure-white colour, it also happens to be low-carb. It’s perfect as a something-different first course for a dinner party or a cosy midweek dinner. It’s so versatile!
Celeriac, that knobbly brown root vegetable that sits quietly in the corner of your grocery store, is an unsung hero in the vegetable world. I thought it’s about time I brought it into the limelight in a dish that stars in this low-carb wonder!
Celeriac is, as you’d guess, part of the celery family. The leaves and stems in fact look just like skinny celery stalks. However you only eat the chunky root bulb of celeriac, and it’s often sold with just this part.
As you’d also guess, it tastes a bit like celery too but with nutty and earthy undertones.
It has a texture like potato when cooked, with a slightly more fibrous quality. Think of it as a low-carb version of potato – it has around 1/3 of the carbohydrates.
Almost anything you can do with potato, you can do with celeriac. Roast it, boil it, mash it, sauté it – and you can even eat it raw if thinly sliced.
Today, we’re soup-ing it! It makes the most wonderfully creamy, silky soup with a texture similar to Pumpkin Soup.
What you need for Celeriac Soup
First up, the vegetables!
Celeriac – You need about 1kg / 2lb whole bulb (unpeeled) to yield 800g/1.6lb after peeling. See below for how to peel and chop celeriac;
Potato – This adds a bit of body and thickness to the soup, being a higher-starch vegetable;
Garlic, onion, celery and leek – The aromatic base for the soup broth, key for getting enough flavour into this soup which is made using just water, no stock (yes, really)!
Next, the rest of the soup:
Water – I like that this soup is made with water rather than stock/broth which many soups call for. This keeps the flavour more pure, instead of tasting similar to every other pureéd soup. The trick to boosting flavour is all the vegetables. This soup has a surprising amount, as you can see above. Sautéing them slowly brings out the flavour;
Cream – Essential for that luxurious mouthfeel and body – especially in the absence of stock – and to give this soup that extra-special touch. I really encourage you not skip it. Remember, the soup is all vegetables other than this cream!!
Yes you can opt for low-fat, or evaporated milk as lower calorie options. But it isn’t quite the same … 🙂 I’ve given some guidance in the recipe notes;
Butter – For sautéing the vegetables;
Herbs and spices – Bay leaf (fresh), thyme, black peppercorns and coriander seeds. These are used to flavour the broth by bundling them up onto a herb and spice sachet. More on why we do this below!
Herb Sachet / Spice Sachet
Called sachet d’épices in French which literally means “bag of spices”, this is used to add flavour into the soup without ending up with little bits of spices in the otherwise clean white soup.
How to make the spice sachet
Just bundle the black peppercorns, coriander seeds, bay leaf and fresh thyme in cheesecloth or muslin, then tie it with a string.
Don’t have cheesecloth? It’s totally not the end of the world! Just amend the recipe as follows (actual quantities given in recipe card):
Use ground coriander instead of whole seeds
Skip the pepper (we already have pepper in the soup)
Thyme sprig and bay leaves – Just add them into the soup and remove before blitzing. The thyme leaves will end up dotted throughout the soup, but to remove then you can easily just strain the soup.
How to cut celeriac
Here’s a quick visual showing how to cut celeriac. Basically, just treat it like a potato and use a peeler! The skin however is a little tougher and rougher than a potato, so you do need to run over the skin a few times to get it all off (those nubbly bits can be a bit annoying!)
You could also cut the skin off with a knife, but you do lose more flesh.
Despite what other sources might tell you, celeriac flesh does not oxidise and go brown very quickly so there’s no need to keep pieces in acidulated water etc.
How to make Celeriac Soup
An unusual and appealing feature of this soup to me is that it’s made with just water rather than stock or broth. However, what this means is that in order to ensure there is enough flavour in the soup, we need to take our time sautéing the vegetables to make them sweet and bring out the flavour in them. So don’t rush the sautéing steps!
Sauté aromatics for 10 minutes – Sauté onion, leek, celery and garlic for 10 minutes until the onion is becomes sweet and translucent but not golden;
Sauté root veg 10 minutes – Add the potato and celeriac and cook for 10 minutes until the outside softens slightly, but again, not golden. Remember, we’re going for a snowy white soup here!
Simmer 25 minutes – Add water and spice sachet containing the herbs and spices (more on this below) then simmer for 25 minutes until the celeriac is very soft;
Cream – Add cream and simmer for just a few minutes;
Blitz! Blend using your method of choice until it’s completely smooth. A stick blender is convenient, but it does take a few minutes and you will need to move it around to blend thoroughly.
Blender option – A blender will be faster but be very careful because hot soup in a full, sealed blender can equal a soup explosion. Literally, you will end up with soup on the ceiling or worse, on you 😫 – been there, done that!
So let the soup cool for 10 minutes or so, then blend in batches as follows: Fill blender about half way, remove cap in the lid so there’s an open hole. Cover the hole with a folded tea towel, then blitz. Transfer to a separate pot/bowl. Repeat to finish all the soup. Now do you see why I opt for a stick blender? 😂
Done! After blitzing, check to see if the salt is to your taste. The 1 1/2 teaspoons called for in this recipe is just perfectly-seasoned to my taste. If you like saltier / restaurant-level seasoning, you’ll need more.
Garnish with croutons (recipe provided) and something green to add a sprinkle of colour – especially chives, parsley or chervil. A little drizzle of olive oil makes a pretty finishing touch too.
What to serve with Celeriac Soup
I feel like hot, buttered crusty bread for dunking goes without saying. Ever-popular Crusty Artisan Bread is just the ticket. Else I wouldn’t say no to a hunk of freshly made Focaccia from last week either. (Both of these happen to be virtually-foolproof-and-no-knead miracle recipes!)
Breads for dunking
How to serve Celeriac Soup
This might sound like a strange instruction – I mean, it’s soup! Everybody knows how to serve soup! 😂
What I actually want to point out here is the different hats this soup can wear. As a lesser-seen vegetable and because of the lovely white colour, it is both interesting and looks very elegant. It would make a nice, sophisticated starter for a seated dinner party. Especially if you have those shallow soup bowls that you often see at fine dining restaurants (I do not, I am all about rustic service!)
But at the same time, the soup is hearty, cosy and filling, and also dead-simple to make. So it’s perfectly good midweek meal or lunch for a cold winter’s day – or something to ladle into a mug and sip as you run around the kitchen making cake to photograph for this Friday’s post. Oh wait, is that just me?? 😂 – Nagi x
PS. I can’t be the only one around here who drinks soup on the go out of mugs. Don’t leave me hanging out to dry on this – tell me if you’re with me!
Watch how to make it
- 60g / 4 tbsp butter , unsalted
- 2 garlic cloves , finely chopped
- 1 onion , diced (brown or yellow)
- 1/2 leek (white part only) , diced into 1cm / ½" cubes (~ 3/4 cup, Note 1)
- 3 celery stems , diced into 1cm / ½" cubes (~1 1/2 cups)
- 800g / 1.6 lb (peeled weight) celeriac , cut into 2cm / ⅘" cubes (~1kg / 2lb unpeeled, Note 2)
- 200g / 7oz potato , peeled, cut into 2cm / 4/5" cubes (floury or all-rounder – about 1 large; Note 3)
- 1.5 litres / quarts (6 cups) water , or stock if you prefer
- 1 1/2 tsp salt
- 1/4 tsp white pepper
- 1 cup cream , full fat (pure, thickened or heavy, Note 4)
Spice Sachet (Note 5):
- 1 bay leaf , fresh
- 2 thyme sprigs
- 1/2 tsp black peppercorn (go without if no sachet)
- 1/2 tsp coriander seeds (1/8 tsp powder if no sachet)
- Croutons (Note 6)
- Olive oil , for drizzling
- 1 tbsp chives , finely chopped (sub parsley or chervil)
- Spice and herb sachet: Bundle the bay leaf, thyme, black peppercorns and coriander seeds loosely in a small piece of cheesecloth to create a sachet. Tie with cooking twine to secure.
- Cook onion and leek: Melt butter in large pot over medium-low heat. Add onion, leek, celery and garlic. Cook for 10 minutes until onion is soft but not golden. Don't rush this part – this creates an important flavour base so we can make this soup using water not stock.
- Cook celeriac and potato: Add celeriac and potato. Cook for 10 minutes, stirring regularly, until the outside of the celeriac and potato starts to soften. Be careful to not colour the celeriac – we're going for a white soup here!
- Simmer 25 minutes: Add salt, pepper, Spice and Herb Sachet, and water. Bring to a boil, then turn down to a simmer. Simmer for 25 minutes (no lid) until celeriac is very soft.
- Cream: Add cream, simmer for another 3 minutes.
- Blitz: Remove Sachet, then blitz until fully smooth using your method of choice: Stick blender (~ 3 mins), or cool slightly and do in a blender in batches (Note 5)
- Adjust seasoning: Adjust salt and pepper to taste.
- Serving: Ladle into bowls. Sprinkle with croutons and chives, drizzle with olive oil. Serve with crusty bread for dunking!
- Low-fat cream – You won’t get the same finish, but this is a simple alternative;
- Veg stock – Make a healthier option by using 1.5L vegetable stock (low sodium) instead of water, and skip the cream and salt; or
- Evaporated milk in place of cream.
More amazing vegetable soups
Life of Dozer
Dozer with his long time girlfriend, Jarrah, owned by one of my best friends! Playing their favourite game – tug of war.
Jarrah was a puppy rescue, so we don’t know what breed she is. But what we do know for sure is that she is a heck of a lot smarter and better behaved than naughty Dozer!