If you’re searching for a soup that’s at once creamy, comforting, and just a little bit luxurious, you’re going to fall head over heels for this Celeriac Leek Soup with Thyme & Gruyère Toasts. Earthy celeriac and sweet leeks blend into a silken base, lifted by the warmth of thyme and the richness of cream. And let’s not forget the Gruyère toasts—golden, melty, and irresistible—made for dunking and savoring with every spoonful. It’s an easy, elegant dish that feels like a special occasion in a bowl, yet couldn’t be simpler to pull together on a chilly evening.
Ingredients You’ll Need
The beauty of Celeriac Leek Soup with Thyme & Gruyère Toasts is how a handful of humble ingredients transform into something deeply flavorful. Each element here plays an essential role, adding complexity, color, and creamy texture to your finished bowl.
- Olive oil (2 tablespoons): Adds fruity richness and helps soften the aromatics without burning.
- Unsalted butter (2 tablespoons): Lends a silky finish and classic French depth to the soup.
- Leeks (2, white and light green parts only), cleaned and sliced: Offer a gentle oniony sweetness and gorgeous pale green color.
- Onion (1 small), chopped: Builds a savory base and blends seamlessly into the soup’s creamy texture.
- Garlic cloves (2), minced: Infuses the soup with subtle, aromatic warmth.
- Celeriac (1 medium, about 1½ pounds), peeled and diced: The star of the show, bringing earthy, nutty notes and a luscious, velvety consistency when blended.
- Potato (1 medium), peeled and diced: Adds body and extra creaminess without overpowering the celeriac.
- Fresh thyme leaves (1 teaspoon, or ½ teaspoon dried): Brightens the soup with herbal, woodsy flavor that ties everything together.
- Vegetable or chicken broth (4 cups): Forms the warming, savory backbone of the soup—use your favorite!
- Whole milk or cream (1 cup): For that luscious finish—use cream for extra richness or milk for a lighter touch.
- Salt and black pepper to taste: Essential for balancing flavors and bringing everything into harmony.
- Baguette (1 small), sliced: The perfect vehicle for gooey Gruyère and a delightful crunch.
- Gruyère cheese (1 cup, shredded): Melts beautifully for toasts that are nutty, creamy, and utterly addictive.
- Fresh thyme leaves (1 teaspoon, for toasts): A fragrant finishing touch for the toasts.
- Olive oil, for brushing: Helps the toasts crisp up to golden perfection under the broiler.
How to Make Celeriac Leek Soup with Thyme & Gruyère Toasts
Step 1: Sauté the Aromatics
Start by heating the olive oil and butter in a large pot over medium heat. As the butter melts and mingles with the oil, add the leeks, onion, and garlic. Cook for 5 to 7 minutes, stirring occasionally, until everything is soft and fragrant but not browned. This gentle sautéing coaxes out the sweetness from the vegetables and creates a deeply flavorful base for your Celeriac Leek Soup with Thyme & Gruyère Toasts.
Step 2: Add the Roots and Thyme
Next, toss in the diced celeriac, potato, and your fresh or dried thyme leaves. Stir well to coat all those chunks in the buttery aromatics. The kitchen will already be smelling incredible, and you’ll start to see a pretty medley of whites and greens in your pot.
Step 3: Simmer with Broth
Pour in your vegetable or chicken broth, crank up the heat to bring it all to a gentle boil, and then lower the heat to a simmer. Let everything bubble away for 25 to 30 minutes, or until the celeriac and potato are meltingly tender. This is when all the flavors meld and the soup takes on its signature heartiness.
Step 4: Blend Until Silky
Take the pot off the heat and use an immersion blender to puree the soup right in the pot until it’s velvety smooth. If you don’t have an immersion blender, carefully transfer the soup in batches to a blender and puree, then return it to the pot. The transformation is magical: what was once chunky and rustic becomes glossy and elegant.
Step 5: Finish with Cream
Stir in the milk or cream and season generously with salt and black pepper. Warm the soup gently over low heat until steaming, but don’t let it boil. This step is where the soup becomes truly luxurious, with a creamy texture that begs for a crust of cheese toast.
Step 6: Make the Gruyère Toasts
Preheat your broiler and arrange the baguette slices on a baking sheet. Brush each slice with olive oil, sprinkle with shredded Gruyère and a little fresh thyme, and pop under the broiler for 1 to 2 minutes. Keep a close eye—when the cheese is bubbling and golden, they’re ready! These toasts are the crowning glory of your Celeriac Leek Soup with Thyme & Gruyère Toasts.
Step 7: Serve and Savor
Ladle the hot soup into bowls and serve with the Gruyère toasts on the side—or float them right on top for a classic French-inspired presentation. Every bite is creamy, cheesy, and absolutely soul-warming.
How to Serve Celeriac Leek Soup with Thyme & Gruyère Toasts
Garnishes
For a beautiful finishing touch, swirl a spoonful of cream into each bowl and sprinkle over extra thyme leaves, a few grinds of black pepper, or even a drizzle of good olive oil. You could also top with crispy shallots or a handful of microgreens for extra color and crunch—each garnish makes your Celeriac Leek Soup with Thyme & Gruyère Toasts feel restaurant-worthy.
Side Dishes
This soup is hearty enough to shine on its own, but a crisp green salad with a tangy vinaigrette makes a refreshing counterpoint. If you’re hosting, pair it with a platter of roasted root vegetables or a simple apple and walnut salad. And don’t forget extra Gruyère toasts—no one will complain about seconds!
Creative Ways to Present
For a dinner party, ladle the soup into small cups for an elegant appetizer, each with a mini Gruyère toast perched on top. Or serve family-style in a big pot at the table, letting everyone help themselves and dunk their toasts as they please. However you present it, Celeriac Leek Soup with Thyme & Gruyère Toasts is a guaranteed conversation starter.
Make Ahead and Storage
Storing Leftovers
Once cooled, transfer leftover soup to an airtight container and refrigerate for up to three days. The flavors deepen as it sits, making tomorrow’s lunch even more delicious. Store Gruyère toasts separately in a zip-top bag at room temperature to keep them crisp.
Freezing
Celeriac Leek Soup with Thyme & Gruyère Toasts is perfect for freezing (just the soup, not the toasts). Let the soup cool completely, then portion into freezer-safe containers, leaving a little room at the top for expansion. It will keep well for up to three months—just defrost overnight in the fridge before reheating.
Reheating
To reheat, pour the soup into a saucepan and warm gently over medium heat until steaming, stirring occasionally. If the soup thickens in the fridge, add a splash of broth or milk to loosen it up. For the toasts, pop them back under the broiler for a minute to revive their crunch and gooey cheese topping.
FAQs
Can I make Celeriac Leek Soup with Thyme & Gruyère Toasts dairy-free?
Absolutely! Swap the butter for additional olive oil, and use your favorite unsweetened plant-based milk (like oat or almond) in the soup. For the toasts, try a vegan cheese that melts well, or simply drizzle the baguette with olive oil and fresh herbs.
What’s the best way to peel celeriac?
Celeriac has a knobby, tough skin, so use a sharp chef’s knife to slice off the top and bottom, then stand it upright and slice downward to remove the skin. Once peeled, dice as needed—it’s much easier than it looks!
Can I use a different cheese for the toasts?
Definitely! While Gruyère adds a nutty, melty quality that perfectly complements the soup, you can substitute with Emmental, Swiss, or even sharp white cheddar. Just choose a cheese that melts beautifully and has good flavor.
How do I prevent the soup from being too thick?
If your Celeriac Leek Soup with Thyme & Gruyère Toasts ends up thicker than you’d like, simply stir in a bit more broth or milk until you reach your preferred consistency. The starch in celeriac and potato naturally thickens the soup, so a little extra liquid goes a long way.
Can I prepare the Gruyère toasts ahead of time?
You can assemble the toasts in advance by brushing the baguette with olive oil and topping with cheese and thyme. Keep them covered at room temperature, then broil just before serving for best results and that irresistible crunchy, gooey finish.
Final Thoughts
If you’re craving something both impressive and soul-soothing, there’s nothing quite like a bowl of Celeriac Leek Soup with Thyme & Gruyère Toasts. It’s the kind of recipe that transforms simple ingredients into a showstopper, perfect for cozy nights or sharing with friends. Give it a try—you just might discover your new favorite soup!
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Celeriac Leek Soup with Thyme & Gruyère Toasts Recipe
- Prep Time: 15 minutes
- Cook Time: 30 minutes
- Total Time: 45 minutes
- Yield: 4 servings
- Category: Soup
- Method: Stovetop
- Cuisine: French-Inspired
- Diet: Non-Vegetarian
Description
A comforting French-inspired celeriac leek soup infused with fresh thyme, blended to a creamy texture and served with crispy Gruyère cheese toasts. Perfect for a cozy fall meal.
Ingredients
Soup Ingredients
- 2 tablespoons olive oil
- 2 tablespoons unsalted butter
- 2 leeks (white and light green parts), cleaned and sliced
- 1 small onion, chopped
- 2 garlic cloves, minced
- 1 medium celeriac (celery root), peeled and diced (about 1 ½ pounds)
- 1 medium potato, peeled and diced
- 1 teaspoon fresh thyme leaves (or ½ teaspoon dried)
- 4 cups vegetable or chicken broth
- 1 cup whole milk or cream
- Salt and black pepper to taste
Gruyère Toasts
- 1 small baguette, sliced
- 1 cup shredded Gruyère cheese
- 1 teaspoon fresh thyme leaves
- Olive oil for brushing
Instructions
- Prepare the Aromatics: Heat the olive oil and butter in a large pot over medium heat. Add the leeks, onion, and garlic and cook for 5–7 minutes until soft but not browned, allowing the flavors to develop.
- Add Vegetables and Thyme: Stir in the diced celeriac, potato, and thyme to coat them evenly with the aromatics, enhancing their flavor.
- Simmer the Soup: Pour in the vegetable or chicken broth. Bring to a boil, then reduce the heat to low and simmer for 25–30 minutes or until the vegetables are tender when pierced with a fork.
- Puree the Soup: Remove the pot from heat and use an immersion blender to puree the soup until smooth. Alternatively, blend the soup in batches in a blender carefully.
- Finish and Season: Stir in the whole milk or cream for creaminess. Season with salt and black pepper to taste. Gently heat the soup until warmed through, avoiding boiling.
- Prepare Gruyère Toasts: Preheat the broiler. Arrange the baguette slices on a baking sheet, brush each slice with olive oil, and sprinkle with shredded Gruyère and fresh thyme leaves.
- Broil Toasts: Place under the broiler for 1–2 minutes or until the cheese melts and turns golden brown, watching carefully to prevent burning.
- Serve: Ladle the hot soup into bowls and serve with Gruyère toasts on the side or floated on top for a delicious contrast of textures.
Notes
- For a dairy-free version, substitute olive oil for butter and use unsweetened plant-based milk instead of cream or whole milk.
- The soup can be made ahead and refrigerated for up to 3 days; reheat gently before serving.
- Use homemade or store-bought vegetable or chicken broth based on your preference to enhance flavor.
- Fresh thyme adds brighter flavor but dried thyme works well as a substitute.
- Adjust seasoning at the end since the cheese toasts add salty richness.
Nutrition
- Serving Size: 1 bowl with 2 toasts
- Calories: 360
- Sugar: 6 g
- Sodium: 520 mg
- Fat: 20 g
- Saturated Fat: 10 g
- Unsaturated Fat: 9 g
- Trans Fat: 0 g
- Carbohydrates: 32 g
- Fiber: 5 g
- Protein: 12 g
- Cholesterol: 35 mg
