Low Calorie Celeriac Soup – with Wicked Blue Cheese Croutons

Last Updated on January 4, 2026

Low-Calorie Celeriac Soup Recipe.

As any regular reader of The Frugal Flexitarian may have noticed, I share recipes for a lot of homemade soup.  Celeriac Soup is one of my own personal favourites – I love the taste of celery, and by using celeriac, I can avoid the stringy bits on normal celery, which you are supposed to remove from your celery with a potato peeler.  And, the root is just that bit more substantial.

You end up with a ‘cream of’ soup without having to add cream (though I do like to stir through a spoonful of creme fraiche just before serving, it’s really not necessary).  So I was delighted when the box of vegetables sent to me by The Organic Pantry contained everything I needed to make a classic celeriac soup.

This kind of recipe, mainly using root vegetables, is one where not only the taste but also the health benefits are remarkably improved by using organic vegetables.  Root vegetables grown in good soil are rich in nutrients and an excellent source of fibre. Celeriac is rich in vitamin K and a good source of vitamin C, Vitamin B⁶, and phosphorus.  But all root vegetables absorb toxins from the soil, so organic is really the best choice where possible.   In my ‘weekly farm box’ from the organic pantry, I received celeriac, Jerusalem artichokes, potatoes, carrots, onions, tenderstem broccoli, cabbage, and leeks.  All of them except the Jerusalem artichokes, tender stem broccoli and cabbage went into this soup, and I added a few ingredients of my own to finish the soup off.

Print Recipe

Celeriac Soup with Blue Cheese Croutons

Prep Time10 minutes mins

Cook Time55 minutes mins

Total Time1 hour hr 5 minutes mins

Course: Lunch, Soup

Cuisine: British

Servings: 6

Calories: 210kcal

Ingredients

• 1 Medium-Large Celeriac Root
• 1 Large Potato
• 1 Medium Brown Onion
• 2 Cloves Garlic
• 50 g Butter (or cooking oil of your choice)
• 1 Large Leek white part only
• 1 Litre Stock I used fresh chicken stock, but you could use vegetable stock or even water
• 100 g Blue Cheese
• 2-3 Slices Left over bread cut into neat cubes
• 1 tbsp Olive Oil
• 1 tbsp Fresh chives
• 6 tsp Creme Fraiche one per serving
• Salt and pepper to taste

Instructions

• Peel and dice the onion and garlic.  Clean and slice the leek.
• Sweat the onion, leek and garlic in a large pan over a low-medium heat for 10 minutes while you prepare the other vegetables
• Peel and dice the potato and celeriac.  Clean thoroughly
• Add to the pan and sweat for 2-3 minutes, stirring frequently
• Add enough stock to the pan to cover all the vegetables with about an inch extra of water. 
• Bring to the boil and simmer gently for 30 minutes, stirring occasionally. Pre-heat the oven to 190C
• Top up with water or stock as necessary and cook until the potato and celeriac is soft and almost falling apart.  
• Blend with a stick blender, season with salt and pepper and cook for a further 5-10 minutes
• Meanwhile, toss the bread cubes for the croutons in the olive oil
• Lay the bread cubes out on a baking tray and sprinkle with blue cheese
• Cook for 5-10 mins till the croutons are crispy and the cheese has melted
• Check the seasoning of the soup and serve with a teaspoon of creme fraiche stirred through each bowlful and with a garnish of croutons and chopped fresh chives.

Nutrition

Calories: 210kcal

Why is this recipe a bit wicked?  Well, you can make a perfectly acceptable lower-calorie version with just the creme fraiche and chives.  You can even sprinkle a little crumbled blue cheese on top (I love that pairing of blue cheese and celery).  But, the nicest version of all, in my opinion, has the lot – a kind of soup sundae with naughty sprinkles.  Oven-baked croutons with olive oil are really not low-calorie at all, and topped with blue cheese, they are actually nice little nibbles on their own.  Added to a celeriac soup, and you have a substantial dish.

This recipe for celeriac soup tastes rich and creamy and is relatively low in calories. The blue cheese adds protein, which will, of course, help to keep you full all day (that’s a good excuse that I am keeping to)

I’m not even going to try to work out the calories in the croutons.  I’m just going to eat this soup two ways—the saintly version, with low-fat creme fraîche for days when I am following an intermittent fasting programme, and the sinful version for feast days!  It looks rather posh, too, doesn’t it, for something made from one of the ugliest vegetables on the supermarket shelf!

Looking for an alternative soup recipe? Try this recipe for spicy tomato and lentil soup

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