Pin It My kitchen smelled like toasted hazelnuts for three days straight after I first made this soup, and honestly, I didn't mind one bit. A friend had left a bag of them on my counter after a farmers market haul, and I was standing there with a head of celeriac, wondering what to do with both. What started as an experiment in using up ingredients became something I've made at least once a month since, usually on those gray afternoons when the weather feels heavy and I need something that tastes like comfort tastes like home.
I made this for my sister on a Sunday when she was going through a rough patch, and she sat at my kitchen table with a bowl of it, steam rising into her face, and just started talking about everything that was bothering her. By the second bowl, she was laughing about something I'd said while reaching for more of that hazelnut crumble. Sometimes food does more than fill your stomach.
Ingredients
- Celeriac: This knobbly root vegetable transforms into something almost buttery when roasted, and roasting first is the secret to actual flavor rather than just bland creaminess.
- Onion and garlic: The aromatic foundation that makes the base smell like something worth eating.
- Potato: Adds body and helps create that signature velvety texture without needing tons of cream.
- Vegetable broth: Use something with actual seasoning, not the bland stuff, because this soup will taste exactly as good as your broth.
- Heavy cream: Optional, but it does add a luxurious finish that's worth it, though plant-based works beautifully too.
- Nutmeg: Just a whisper of it, enough to make people wonder what's making their spoon pause.
- Hazelnuts: These get toasted until they're golden and fragrant, which is entirely different from eating them raw from a bag.
- Butter: For the crumble, though olive oil works if you're keeping it vegan.
- Parsley: Fresh, finely chopped, and stirred in at the last second so it stays bright green and herbaceous.
Instructions
- Roast the celeriac until it's golden:
- Preheat your oven to 200°C, toss those diced pieces with olive oil, and spread them out so they're not crowding each other. They'll need 25 to 30 minutes, and turning them halfway through means they get color on all sides.
- Build your flavor base:
- In a large pot, warm olive oil over medium heat and add the onion and garlic, letting them soften together for a few minutes until they start to smell like the beginning of something good.
- Combine everything and simmer:
- Add your roasted celeriac and the diced potato, pour in the broth, and bring it to a boil before lowering the heat. This will take 15 to 20 minutes of gentle simmering until the vegetables are so soft they practically dissolve.
- Toast the hazelnuts while the soup cooks:
- In a small skillet, melt the butter over medium heat and add the roughly chopped hazelnuts, watching them carefully as they toast for about two to three minutes until the smell becomes intoxicating and they turn a deeper brown. Stir in the parsley and salt, then set aside.
- Blend until it's completely smooth:
- Using an immersion blender, puree the soup right there in the pot, or work in batches with a stand blender if you prefer. The goal is silky, not a single lump remaining.
- Finish with cream and spices:
- Stir in the cream if you're using it, add the nutmeg, salt, and pepper, and warm it gently until it's steaming and ready to serve.
- Serve with the crumble on top:
- Ladle the soup into bowls and scatter that hazelnut mixture generously across the top, letting people break through the crunch with their first spoonful.
Pin It 
There was a moment when I was blending this soup for the third or fourth time and my roommate came home, stopped in the doorway, and just closed their eyes while breathing in. They didn't even ask what I was making, just sat down at the counter like they belonged there, and suddenly I wasn't just making soup anymore, I was making an invitation.
The Magic of Roasting
I used to skip the roasting step and go straight to boiling everything together, thinking it was just one more pan to wash. The difference between that version and this one is the difference between okay and actually wanting seconds. Roasting concentrates the flavors and adds a subtle sweetness that no amount of seasoning can replicate, so please don't skip it even if you're in a hurry.
Making It Your Own
This soup is forgiving enough that you can swap in other nuts if hazelnuts aren't your thing, or add a splash of white wine to the base for extra depth. I've made it with almonds, with walnuts, and even toasted pumpkin seeds when someone mentioned a nut allergy. The structure stays solid, but the flavor becomes entirely your own interpretation.
Serving and Storage Wisdom
This soup keeps beautifully in the fridge for four or five days, though the hazelnut crumble is best made fresh right before serving because it softens over time. I like reheating it gently on the stove with a splash of broth or cream to refresh it, and it pairs perfectly with crusty bread for wiping the bowl clean.
- Make the hazelnut crumble just before serving so it stays crunchy and doesn't get soggy from the steam.
- If you're doubling the recipe for a crowd, the soup freezes beautifully without the cream, so you can defrost and finish it whenever you need it.
- A drizzle of hazelnut oil or a handful of fresh sage leaves on top takes it from comforting to almost fancy enough for guests.
Pin It This soup has become my go-to when I want to feed someone without it feeling like trying too hard, or when I want to feed myself and feel looked after. There's something about a bowl of it that makes ordinary evenings feel a little less ordinary.
Recipe Questions & Answers
- → What does celeriac taste like?
Celeriac offers a mild, sweet flavor with subtle celery notes and earthy undertones. When roasted, these qualities concentrate and become richer, making it more complex than raw preparations.
- → Can I make this soup ahead of time?
Absolutely. The base keeps refrigerated for up to 3 days and actually develops more flavor. Reheat gently, adding a splash of liquid if needed. Prepare the crumble fresh and sprinkle just before serving for maximum crunch.
- → How do I achieve the smoothest texture?
Roasting the celeriac first is key—it breaks down fibers naturally. Blend thoroughly with an immersion blender for several minutes, passing through a fine-mesh sieve if you want restaurant-quality silkiness.
- → What can I substitute for hazelnuts?
Toasted walnuts or pecans work beautifully, offering similar richness and crunch. For nut-free versions, try toasted pumpkin seeds or crispy fried shallots for that essential textural contrast.
- → Is the cream necessary?
Not at all. The potato provides natural creaminess when blended, creating satisfying body without dairy. Plant-based creams work equally well if you prefer vegan options while maintaining that luxurious mouthfeel.
- → Why roast the celeriac instead of boiling?
Roasting caramelizes the natural sugars in celeriac, creating deeper flavor and golden color. This extra step transforms what could be a simple preparation into something notably complex and satisfying.