Save to Pinterest The smell of roasted celeriac is something that still catches me off guard every time, earthy and faintly sweet, like autumn condensed into a single vegetable. I used to walk right past it at the market, assuming it was too strange or too much work. Then a neighbor handed me one with no explanation, just a wink, and I decided to trust her. That night, I roasted it until the edges caramelized, blended it into something silky, and understood immediately why she smiled. The hazelnut crumble came later, born from a happy accident when I burned breadcrumbs and grabbed nuts instead.
I made this for a small dinner party on a drizzly October evening, the kind where everyone arrives damp and grateful for warmth. The kitchen fogged up as I blended the soup, and someone wandered in asking what smelled so good. When I served it with the crumble scattered on top, the table went quiet for a moment, just the sound of spoons against bowls. One friend, who claimed to hate celery, had two servings and asked for the recipe before dessert even arrived.
Ingredients
- Celeriac: This knobby root becomes sweet and nutty when roasted, so do not skip that step or you will miss the depth it brings to the soup.
- Onion: A simple base that melts into the background, adding gentle sweetness without competing with the star ingredient.
- Garlic: Just enough to add warmth and a whisper of sharpness, balancing the earthiness of the celeriac beautifully.
- Potato: Acts as a natural thickener, giving the soup body and a velvety texture without needing flour or cream alone.
- Vegetable broth: Use a good quality broth here because it forms the backbone of the flavor, and a weak one will make everything taste flat.
- Olive oil: For roasting and sautéing, it adds a subtle fruity note that rounds out the vegetables.
- Heavy cream: Stir it in at the end for richness, or use a plant based version if you prefer, either way it adds silky smoothness.
- White pepper: Milder than black and it keeps the soup pale and elegant, though black pepper works if that is what you have.
- Hazelnuts: Toasted until fragrant and tossed with butter and salt, they become the crunchy, nutty contrast this soup was made for.
- Parsley: A fresh, green finish that brightens each bowl and makes the whole dish look alive.
Instructions
- Roast the Celeriac:
- Preheat your oven to 200°C and toss the celeriac cubes with olive oil, salt, and pepper, then spread them on a baking tray. Roast for 25 to 30 minutes, turning them halfway through, until they are golden and tender with caramelized edges.
- Sauté the Aromatics:
- While the celeriac roasts, heat olive oil in a large pot over medium heat and cook the onion for about 4 minutes until it turns translucent. Add the garlic and diced potato, stirring for another 2 minutes until fragrant.
- Simmer the Soup:
- Transfer the roasted celeriac into the pot with the onion and potato, then pour in the vegetable broth and bring everything to a gentle boil. Let it simmer for 15 to 20 minutes until all the vegetables are very soft and breaking apart easily.
- Prepare the Hazelnut Crumble:
- Toast the chopped hazelnuts in a dry skillet over medium heat for 3 to 4 minutes, shaking the pan often until they smell nutty and turn golden. Add the butter and sea salt, stirring until the nuts are evenly coated, then remove from heat and let them cool slightly.
- Blend Until Silky:
- Use an immersion blender directly in the pot, or carefully transfer the soup in batches to a countertop blender, and purée until completely smooth. Stir in the cream if using, then taste and adjust the salt and pepper to your liking.
- Serve and Garnish:
- Ladle the hot soup into bowls and top each serving generously with the hazelnut crumble and a sprinkle of fresh parsley. Serve immediately while the crumble is still warm and crisp.
Save to Pinterest This soup became my go to whenever I needed something comforting but impressive, the kind of dish that feels like a hug but also makes people lean in and ask questions. I have served it to skeptics who wrinkled their noses at the mention of celeriac, and watched them scrape their bowls clean. It is proof that the weird, forgotten vegetables in the corner of the market often have the best stories to tell.
Making It Your Own
You can add a sprig of fresh thyme to the pot while it simmers for a woodsy, herbal note that pairs beautifully with the earthiness of the celeriac. A squeeze of lemon juice just before serving brightens the whole bowl and cuts through the richness if you are skipping the cream. I have also stirred in a spoonful of miso paste for umami depth, which sounds odd but works surprisingly well. If you want more texture, try adding roasted chickpeas or crispy shallots alongside the hazelnut crumble.
Storage and Reheating
The soup keeps beautifully in the fridge for up to four days, stored in an airtight container, and it actually tastes even better the next day once the flavors have melded. Reheat it gently on the stovetop over low heat, stirring occasionally, and add a splash of broth or water if it has thickened too much. The hazelnut crumble, however, should be stored separately in a sealed container at room temperature and added fresh to each serving to keep it crunchy. I have frozen the soup without the cream for up to two months, then stirred in fresh cream after thawing and reheating.
Serving Suggestions
This soup shines as a starter for a dinner party, especially in the cooler months when something warm and earthy feels just right. Serve it with crusty sourdough bread or a simple green salad dressed with lemon and olive oil to keep things light. A dry white wine like Pinot Gris or a crisp Chardonnay complements the nutty, creamy flavors without overwhelming them.
- Pair it with roasted chicken or a sharp aged cheese for a more substantial meal.
- Drizzle a bit of truffle oil over the top for an elegant, luxurious touch.
- Garnish with toasted pumpkin seeds or croutons if you cannot find hazelnuts.
Save to Pinterest This is the kind of soup that makes you slow down and savor, the kind that reminds you why cooking from scratch matters. I hope it brings warmth to your table the way it has to mine.
Common Recipe Questions
- → Why roast the celeriac instead of boiling it?
Roasting develops deeper, caramelized flavors and brings out the celeriac's natural sweetness through the Maillard reaction. This creates a richer, more complex soup compared to boiling, which can result in a watery, bland purée.
- → Can I make this soup ahead of time?
Yes, the soup keeps refrigerated for up to four days in an airtight container. The hazelnut crumble is best prepared fresh or stored separately for up to two days in an airtight jar. Reheat the soup gently over low heat, adding a splash of broth if needed to restore consistency.
- → What can I substitute for hazelnuts?
Almonds, walnuts, or pecans work beautifully as alternatives. You can also try toasted breadcrumbs mixed with herbs for a crispy topping, or crushed pumpkin seeds for a different textural element.
- → How do I achieve the smoothest texture?
An immersion blender gives the silkiest results when blending directly in the pot. For a countertop blender, work in batches and avoid overfilling. Blend for a full minute or two until completely smooth. For ultra-refined texture, pass through a fine-mesh sieve after blending.
- → Is this suitable for freezing?
The soup freezes well for up to three months in freezer-safe containers, leaving an inch of headspace for expansion. Thaw overnight in the refrigerator and reheat gently. The hazelnut crumble should not be frozen; prepare it fresh before serving.
- → What flavors pair well with celeriac?
Thyme, sage, and bay leaf enhance its earthiness. A squeeze of fresh lemon juice adds brightness without overpowering. Nutmeg or white pepper provide subtle warmth. A drizzle of truffle oil elevates this soup for special occasions.