Celeriac Soup With Hazelnut Crumble

My neighbor arrived at the farmers market with a celeriac so enormous it barely fit in her bag, insisting I had to try making soup with it. I was skeptical at first—the knobby root vegetable looked more like something from a root cellar than dinner—but the moment that oven-roasted celeriac hit the broth, the kitchen filled with this warm, almost nutty sweetness that changed my mind completely. What started as curiosity turned into a ritual, especially on those grey afternoons when I needed something both elegant and deeply comforting. The hazelnut crumble was the happy accident that sealed it—a way to add that textural contrast I didn't know I was missing.

I made this for my sister when she mentioned being tired of heavy cream-based soups, and watching her taste it was one of those quiet moments that reminded me why cooking matters. She closed her eyes for a second, then immediately asked if I'd done something special with the hazelnuts—there's something about that toasted, buttery crunch that elevates the whole experience from nice soup to something memorable.

Ingredients

• Celeriac (about 700 g, peeled and diced): The star of the show—roasting it first brings out a subtle sweetness that raw would miss entirely.
• Potato (about 150 g, peeled and diced): Adds body and creaminess without cream, something I learned after one batch turned out a bit too thin.
• Onion and garlic (1 medium onion, 2 cloves): The aromatics that build flavor from the ground up, best sautéed until they soften and turn golden.
• Vegetable broth (900 ml): Use something you'd actually drink—the quality makes a real difference in the final taste.
• Olive oil (2 tbsp total): One tablespoon for roasting the celeriac, one for sautéing, keeps everything light and lets the vegetables shine.
• Heavy cream or plant-based cream (100 ml, optional): This is optional but does add richness; if skipping, the soup is still silky from the potato.
• Sea salt and freshly ground black pepper: Always taste and adjust—salt brings out all the subtle flavors hiding in that celeriac.
• Ground nutmeg (1/4 tsp): Just a whisper of it, the kind of spice that makes people wonder what that warm note is.
• Whole hazelnuts (60 g, roughly chopped): Buy them raw if you can and toast them yourself—the aroma alone is worth it.
• Unsalted butter or olive oil for the hazelnut crumble (1 tbsp): Butter gives a more luxurious toasting, but oil works perfectly for vegan versions.
• Fresh parsley (1 tbsp, finely chopped): Adds a bright note that cuts through the richness and keeps things feeling fresh.

Instructions

Get the oven ready and start roasting:

Preheat to 200°C and spread your diced celeriac on a baking sheet, toss it with 1 tablespoon of olive oil until everything glistens, then slide it into the oven. Turn the pieces once about halfway through those 25–30 minutes—you're looking for edges that are golden and caramelized, which is where all the depth of flavor lives.

Build your flavor base in the pot:

While the celeriac is in the oven, heat 1 tablespoon olive oil in a large pot and let your diced onion and minced garlic soften for 3–4 minutes, stirring occasionally. The kitchen will smell incredible—this is the moment you know something good is happening.

Combine and simmer:

Once the celeriac comes out of the oven, add it to the pot along with the diced potato and pour in your vegetable broth. Bring everything to a boil, then drop the heat down and let it simmer gently for 15–20 minutes until the vegetables are completely soft and surrender easily to a spoon.

Toast the hazelnuts while you wait:

In a small skillet, melt your butter and add the roughly chopped hazelnuts, toasting for 2–3 minutes until they turn golden and smell absolutely fragrant. Stir in the parsley and a pinch of salt, then set it aside—this is your finishing touch.

Blend until silky smooth:

Once the soup vegetables are tender, use an immersion blender right in the pot to puree everything until completely smooth, or carefully transfer to a blender in batches if you prefer. The texture should be velvety enough that it coats the back of a spoon.

Season and finish:

Stir in the cream if you're using it, add the nutmeg, salt, and pepper to taste—this is where you balance everything out. Reheat gently if needed, but don't let it boil once the cream is in.

Serve with the crumble:

Ladle the soup into warm bowls and sprinkle generously with that hazelnut crumble while it's still warm, so the warmth of the soup slightly softens the nuts just enough.

Save

There was an evening when a friend who'd been going through a difficult time came by, and I made this soup almost without thinking. Halfway through the bowl, she mentioned it was the first meal in weeks that actually felt like comfort instead of just fuel—that's when I understood that this recipe is about more than technique, it's about showing up for people with something warm and genuine.

The Magic of Roasting Root Vegetables

I used to think all soup required heavy cream or butter to feel luxurious, but roasting the celeriac first taught me otherwise. That caramelization creates natural sweetness and depth that makes the whole soup richer without needing anything heavy. The potato adds silkiness too—it breaks down into the broth and creates this lovely velvety texture that feels indulgent even though you're just using vegetables and broth.

Why the Hazelnut Crumble Matters

The first time I made this soup without any topping, it was perfectly fine but somehow felt incomplete. Adding that warm hazelnut crumble changed the entire experience—suddenly there's texture, a hint of nutty richness, and something that makes you want another spoonful. It's also the part that people remember and ask about, which tells you something about how important contrast is in a dish.

Adaptations and Personal Touches

This recipe is forgiving in the best ways—I've made it with parsnip added in, with a drizzle of hazelnut oil at the end, even topped it with crispy sage leaves instead of parsley. Each time it feels slightly different but equally comforting, which is exactly what I want from a soup that earns its place in regular rotation.

• For a gourmet touch, finish with a small drizzle of hazelnut oil and a few extra toasted nuts.
• If you want more herbaceous notes, try adding fresh thyme or tarragon to the broth while it simmers.
• Crusty bread is essential—it's not optional, it's how you get the most out of every spoonful.

Save

This soup has become one of those recipes I reach for when I want to make something that feels both simple and special. It's proof that sometimes the most memorable meals come from listening to what ingredients tell you they want to become.

Recipe FAQs

→ Can I make this soup ahead of time?

Yes, prepare the soup up to 3 days in advance and store in the refrigerator. Make the hazelnut crumble fresh just before serving to maintain its crunch.

→ How do I make this vegan?

Simply substitute plant-based cream for heavy cream and use olive oil instead of butter in the hazelnut crumble. The flavor remains rich and delicious.

→ What does celeriac taste like?

Celeriac has a mild, celery-like flavor with subtle nutty and earthy notes. Roasting enhances its natural sweetness and removes any bitterness.

→ Can I substitute other nuts for hazelnuts?

Absolutely. Toasted almonds, walnuts, or pecans work beautifully. Each brings its own unique flavor profile to complement the soup.

→ Why add potato to the soup?

Potato adds body and natural creaminess, creating a velvety texture when blended. It also helps balance the distinct flavor of celeriac.

→ Can I freeze this soup?

Yes, freeze the soup without cream for up to 3 months. Thaw, reheat gently, then stir in cream. Always make the crumble fresh.