Save There's something about the smell of leeks hitting hot butter that makes a kitchen feel instantly lived-in. My neighbor Sarah brought me a bunch of overgrown leeks from her garden one chilly October afternoon, and instead of letting them sit in the crisper drawer like I usually do, I decided to finally make that soup I'd been thinking about. What started as a quiet afternoon project turned into the kind of meal that makes you want to sit at the table longer than necessary, just to be warm and full.
I brought this soup to a friend's dinner party once, nervous it was too simple for the occasion, but it disappeared faster than the fancy salad. By the time dessert rolled around, someone was asking for the recipe, and I realized that sometimes the best dishes are the ones that don't try too hard to impress.
Ingredients
- Leeks (3 large, white and light green parts): These are where the magic happens, so don't skip the cleaning step or you'll find grit in every spoonful.
- Russet potatoes (3 medium, peeled and diced): They break down into the cream beautifully and make the soup naturally thick without any flour or cornstarch.
- Yellow onion (1 medium, diced): This builds the flavor foundation alongside the leeks, adding sweetness as it softens.
- Garlic (2 cloves, minced): Just enough to whisper in the background without overpowering the delicate leek flavor.
- Unsalted butter (3 tablespoons): The first thing that hits the pot, creating the base for sautéing everything else.
- Heavy cream (1/2 cup): Added at the end to give the soup that restaurant-quality velvety texture, or use milk or plant-based cream if that's what you have.
- Vegetable broth (5 cups): The backbone of the soup, so use something you'd actually drink on its own.
- Salt and freshly ground black pepper: Taste as you go because seasoning is everything in a soup this simple.
- Sourdough bread (2 cups, cut into half-inch cubes): Day-old or slightly stale bread works better than fresh because it crisps up instead of turning to mush.
- Olive oil (2 tablespoons): For toasting the croutons until they're golden and crunchy on the outside.
- Dried thyme (1/2 teaspoon): Just a hint of earthiness that complements leeks without competing with them.
- Sea salt (1/4 teaspoon): A light sprinkle on top of the croutons before baking brings out their flavor.
- Fresh chives (2 tablespoons, chopped): The final garnish that adds a fresh onion note and a pop of green color.
Instructions
- Get your oven ready and prep the croutons:
- Preheat to 375°F while you handle the soup prep, because the croutons and soup need to work on overlapping timelines. Toss your sourdough cubes with olive oil, thyme, and sea salt, spread them on a baking sheet, and set aside until the soup is simmering.
- Start with the aromatics:
- Melt butter in a large pot over medium heat until it's foaming and smells nutty. Add your sliced leeks, diced onion, and minced garlic, stirring occasionally for 6 to 8 minutes until everything is soft and translucent but hasn't taken on any color.
- Bring the potatoes into the picture:
- Add your diced potatoes and let them cook with the aromatics for 2 minutes, which helps them absorb all those buttery flavors. The potatoes will do most of the heavy lifting for making the soup creamy, so don't skip this step.
- Build the soup base:
- Pour in your vegetable broth, season generously with salt and pepper, then bring everything to a gentle boil. Lower the heat, cover the pot, and let it simmer for about 20 minutes until the potatoes are completely tender and fall apart easily with a spoon.
- Bake the croutons while you wait:
- About halfway through the soup's cooking time, slide your seasoned bread cubes into the oven and let them toast for 10 to 12 minutes, stirring them once so they brown evenly. They're done when they're golden all over and make a crisp sound when you tap them.
- Blend the soup into silky perfection:
- Remove the pot from heat and use an immersion blender to blend everything until smooth and creamy, or carefully transfer it in batches to a countertop blender and then return it to the pot. The warmth of the soup makes this easier than you'd expect, and the result is incredibly luxurious.
- Finish with cream and final seasoning:
- Stir in the heavy cream, then gently reheat the soup without letting it boil, which can cause the cream to separate. Taste and adjust the salt and pepper one more time because this is your last chance to get it exactly right.
- Serve with all the trimmings:
- Ladle the soup into bowls, top each one with a generous handful of the crispy sourdough croutons, and finish with a sprinkle of fresh chives. The croutons should stay on top where they stay crunchy instead of sinking in and getting soggy.
Save My kid came home from school one rainy day and immediately asked if I was making that soup again because the smell had traveled down the hallway. Something about this soup has a way of making people feel cared for without any fuss, which might be the best quality any recipe can have.
The Secret to Silky Texture
The texture of this soup comes entirely from the potatoes breaking down and the blending process, not from any thickening agent, which means it tastes cleaner and lighter than you'd expect. When you blend a warm soup made mostly of potatoes and cream, you get this naturally luxurious mouthfeel that feels indulgent without being heavy. The key is making sure your potatoes are genuinely tender before you blend, otherwise you'll end up with little chunks instead of that perfect smoothness.
Timing Your Croutons Right
The best part about this recipe is that the croutons and soup finish at almost exactly the same time if you time it right, which means you can assemble everything while it's all still hot. I used to make croutons ahead of time and they'd lose their crispness, but baking them while the soup simmers means they're at their peak when you need them. If you're worried about coordination, you can definitely make the croutons earlier in the day and reheat them in a 300°F oven for a few minutes before serving.
Making It Your Own
This is one of those recipes that becomes a different dish depending on what you add to it, which is why I keep making it over and over without getting bored. A handful of fresh spinach stirred in at the end turns it green and adds a slightly peppery note, while watercress makes it feel fancier and more bitter in the best way. Some people swear by a splash of white wine stirred in with the cream, and honestly, they're onto something because it adds brightness that makes the soup feel more sophisticated.
- Try a thin slice of crispy bacon crumbled over the top if you want to make it less vegetarian but absolutely unforgettable.
- A tiny drizzle of truffle oil or a sprinkle of Gruyère cheese turns this into something you'd serve at a dinner party without apology.
- Save any leftover soup in the fridge for up to three days, though the croutons are best added fresh right before you eat it.
Save This soup has become the thing I make when I want to feel like I'm taking care of someone, including myself. It's proof that the best recipes don't need to be complicated to feel special.
Cooking Guide
- → What is the best way to clean leeks for this dish?
Trim off the roots and dark green tops, slice the white and light green parts, then soak in cold water to remove any dirt or grit before rinsing thoroughly.
- → Can I substitute the heavy cream for a lighter option?
Yes, you can use milk or plant-based cream alternatives to keep it lighter while maintaining a creamy consistency.
- → How should the sourdough croutons be prepared for optimal texture?
Toss sourdough cubes in olive oil, thyme, and sea salt, then bake at 375°F (190°C) for 10–12 minutes until golden and crisp, turning once.
- → Is it necessary to blend the soup until smooth?
Blending creates the desired velvety texture, but if preferred, leaving some chunks provides a rustic feel.
- → How can I adjust this dish for a vegan diet?
Use plant-based butter and cream substitutes to replace dairy ingredients without sacrificing richness.
