Save There's something about the sound of leeks hitting hot butter that signals comfort is on the way. One rainy afternoon, my neighbor stopped by with a bunch of leeks from her garden, and I found myself drawn to this soup almost by accident—no grand plan, just the feeling that something warm and velvety was needed. The result was so silky it surprised us both, especially when those golden croutons hit the bowl and brought everything to life with a satisfying crunch.
I made this for a small dinner party once, and the moment everyone tasted it, the room went quiet in that way that means the food is doing its job. Someone asked if I'd been cooking it all day, and I loved admitting it was ready in under an hour. That's when I knew this recipe had become one of my go-to moves.
Ingredients
- 3 large leeks (white and light green parts only): Leeks are milder and sweeter than onions once cooked, and they give this soup a gentle sophistication. The white and light green parts are tender; save the dark greens for broth another time.
- 3 medium russet potatoes: They break down into the liquid and create that natural creaminess without needing extra cream—though we add it anyway because why not.
- 1 medium yellow onion: A supporting player that deepens the flavor without overpowering the delicate leeks.
- 2 cloves garlic: Just enough to whisper in the background, not shout.
- 2 tablespoons fresh chives: A bright, onion-forward garnish that adds a fresh note right at the end.
- 3 tablespoons unsalted butter: Use real butter here; it makes a difference in how the leeks soften and the soup tastes overall.
- 1/2 cup heavy cream: You can use milk or plant-based cream if you prefer, but heavy cream creates that restaurant-quality richness.
- 5 cups vegetable broth: A good quality broth is worth seeking out—it sets the flavor foundation.
- Salt and freshly ground black pepper: Season as you taste, not all at once.
- 2 cups sourdough bread, cut into 1/2-inch cubes: Sourdough holds its texture and adds a subtle tang that plays beautifully against the creaminess.
- 2 tablespoons olive oil: For toasting the croutons until they're golden and crisp.
- 1/2 teaspoon dried thyme: Thyme and potatoes are old friends; this amount seasons the croutons without overshadowing them.
- 1/4 teaspoon sea salt: A finishing salt for the croutons brings out their toasted flavor.
Instructions
- Get Your Croutons Started:
- Turn your oven to 375°F while you work on the soup base. This way they bake at the same time and everything comes together at once, hot and ready to eat.
- Build the Flavor Base:
- Melt butter in a large pot over medium heat, then add your sliced leeks, diced onion, and minced garlic. You're looking for that moment when they become soft and fragrant, about 6 to 8 minutes, but stop before they brown—you want sweetness here, not caramelization.
- Add the Potatoes:
- Toss in your diced potatoes and stir everything together for just 2 minutes so they pick up the buttery flavor.
- Simmer Until Tender:
- Pour in the vegetable broth, season with salt and pepper, and bring it to a gentle boil. Lower the heat, cover the pot, and let it simmer for 20 minutes until the potatoes are completely fork-tender and starting to fall apart.
- Toast Those Croutons:
- While the soup simmers, toss your sourdough cubes with olive oil, dried thyme, and sea salt, then spread them on a baking sheet. Bake for 10 to 12 minutes, stirring halfway through, until they're golden and crisp all over.
- Make It Smooth:
- Once the potatoes are done, remove the pot from heat and use an immersion blender to blend everything into a smooth, velvety texture. If you don't have an immersion blender, carefully transfer the soup in batches to a countertop blender, then pour it back into the pot.
- Finish with Cream:
- Stir in the heavy cream and gently reheat the soup without letting it boil—boiling can break the cream and change the texture. Taste and adjust your seasoning if needed.
- Serve and Celebrate:
- Ladle the soup into bowls, pile those crispy croutons on top, and finish with a sprinkle of fresh chives. Serve immediately while everything is warm and the croutons still have their snap.
Save This soup taught me that the simplest dishes often carry the most warmth. It's become the thing I make when someone needs comfort, when the weather turns cold, or when I want to prove that good food doesn't require hours in the kitchen.
Why Leeks and Potatoes Are a Classic Pairing
Leeks have this mellow sweetness that potato's earthiness craves, and together they create a soup that feels substantial but never heavy. The potato breaks down and thickens everything naturally, while the leek stays gentle and refined. I used to think I needed lots of cream to make soup feel luxurious, but this combination proved me wrong—the vegetables themselves do most of the work.
The Crouton Secret
People always ask what makes these croutons different from the sad ones you get from a bag. It's the sourdough—that slight tang and chewy structure holds up to the oven heat and stays crisp instead of getting soggy. The thyme adds an herbaceous note that makes people wonder what your secret ingredient is, and olive oil with sea salt creates a finish that tastes intentional, not bland.
Making It Your Own
Once you've made this soup a couple of times, you'll find yourself tweaking it naturally. A handful of fresh spinach stirred in at the end turns it green and adds iron, while a few drops of truffle oil transforms it into something for special occasions. Some people add a splash of dry white wine before the broth for extra depth, and others crisp up sage leaves instead of using thyme on the croutons.
- For a vegan version, swap the butter for olive oil and the cream for a plant-based option—the soup loses nothing in translation.
- Make the croutons ahead of time and store them in an airtight container; they stay crisp for a few days and make reheating even easier.
- This soup freezes beautifully, so make a double batch and have comfort waiting for you on harder days.
Save This recipe became my answer to almost every question: What should I cook tonight? What can I bring to someone? What feels right for a quiet dinner? It's one of those dishes that reminds you why cooking for yourself and others matters so much.
Recipe Questions
- → What type of leeks should I use?
Use the white and light green parts of leeks, cleaned thoroughly to remove any grit for the best texture.
- → Can I substitute heavy cream in this dish?
Yes, you can use milk or plant-based cream alternatives to achieve a similar creamy finish.
- → How do I make the croutons crispy?
Toss sourdough cubes with olive oil, thyme, and sea salt, then bake at 375°F for 10–12 minutes until golden and crisp.
- → Is it possible to prepare this dish vegan?
Absolutely, replace butter and cream with plant-based versions to keep the dish vegan-friendly.
- → What cooking tools are needed?
A large pot for simmering, an immersion or countertop blender for blending, and a baking sheet for croutons will be required.
