This sweet and creamy butternut squash and leek soup embodies all the Fall vibes. It takes a little more time to caramelize the vegetables, but the added depth of flavor will take your soup to the next level. And since we're making it from scratch, I'll tell you how to select the best squash and leeks for the best flavor and easier preparation.
Butternut squash leek soup is perfect for Fall, as the weather turns cooler. I find myself craving a hot bowl of creamy, nourishing soup during these shorter days. Plus its bright orange color breaks up the mundanity of the seemingly endless gray clouds here in the PNW this time of year. It’s like a big, warm hug in a bowl!
The secret to making this soup a knock-out is roasting the butternut squash and leeks in the oven before adding them to your pot. This gives them a deliciously rich caramelized flavor!
I love serving this soup for my family as a full meal alongside grilled cheese sandwiches, crusty toasted bread like my German farmer's bread, or chicken Caesar salad.
And if you're looking for more delicious soup recipes for Fall, try my chickpea soup, roasted butternut squash and carrot soup, and vegetable bean chili.
Ingredients and Substitutions
- Butternut squash - You could substitute other winter squashes like acorn squash or pumpkin.
- Leeks - When roasted, they soften and develop a buttery flavor.
- Olive oil
- Kosher salt - I recommend using kosher salt since it disperses quickly and has a better flavor than table salt. But if you only have table salt, cut the measurement of salt in half, since kosher salt grains are much bigger.
- Unsalted butter
- Garlic - I recommend using freshly minced garlic cloves for the most potent flavor. You can swap in about one teaspoon of garlic powder.
- Dried thyme - If you have fresh thyme instead, use one tablespoon of the leaves and make sure you remove any stems.
- Ground black pepper
- Vegetable broth - You could swap in chicken broth or beef broth.
- Coconut milk - Thickens the soup and adds more creamy texture. You could substitute heavy cream.
My Tips on Picking a Good Butternut Squash
- Whole: While peeled and pre-cut squash is more convenient, a whole, uncut squash will last longer and they usually have a fresher flavor.
- Texture: Select a squash that is firm and heavy with smooth skin.
- Color: Butternut squash should be beige or tan. Don't get one with green patches, which probably means it isn't ripe.
- Stem: Don't select a squash with a moldy stem. Pick one with a firm, dry stem.
- Shape: The neck is usually thinner and longer than the more round bottom of the squash. The more uniformly it's shaped, the easier it will be to scoop out the flesh from the skin.
Let's Make this Soup Together!
Below are the general steps to make this butternut squash and leek soup. For the full step-by-step directions and ingredient measurements, scroll down to the recipe card at the bottom of this post.
1. Cut the butternut squash in half lengthwise.
3. Slice the white and tender green parts of the leeks into one-inch chunks.
5. Spread the leeks and squash halves cut-side-down on a baking sheet.
7. Melt the butter in a large pot on medium-low heat.
9. Scrape out the squash and discard the skin. Add the roasted squash and leeks to the pot.
11. Blend the soup until it's creamy.
2. Scoop out the seeds and string stuff from inside.
4. Toss the leeks in a small bowl with the olive oil and ¼ teaspoon of salt.
6. Bake the butternut squash and leeks, until both are easily pierced with a fork.
8. Add the minced garlic and cook until it smells really fragrant.
10. Add thyme, pepper, salt, broth, and coconut milk. Boil, then simmer for 20 min.
12. To serve, ladle into bowls and add any garnishes you like. Enjoy!!
Recipe Tips
- Spicy: To add a kick of heat, add a quarter teaspoon of cayenne pepper or a half teaspoon of smoked paprika.
- Onions: If you don’t have leeks, you can substitute shallots or sweet onions. I still recommend roasting them in the oven, but watch them closely, as they may cook faster than the squash. Alternatively, you could sauté them in olive oil or butter on the stove.
- Herbs: Instead of thyme, you could use rosemary or sage.
- Blending: I usually blend my soup right in the pot with an immersion blender. But if you blend hot soup in a regular blender, it’ll build up pressure and could cause the soup to explode! So let your soup cool a bit, and let it vent out the top, with a towel covering the top to catch any splatters.
Storing
Fridge: Allow leftover soup to cool completely. Store in the fridge in airtight containers for up to 4 days.
Freezer: Allow leftover soup to cool completely. Store in the freezer in airtight containers for up to 3 months.
Frequently Asked Questions
Do you leave the skin on butternut squash for soup?
Technically the skin is edible, but it's really tough and fibrous, and I don't think it's very pleasant to eat. Therefore, I recommend to remove and discard the skin after the squash has been roasted.
What to garnish the soup with?
You can leave this soup plain, or garnish it with roasted pumpkin seeds, a dollop of cream or coconut milk, homemade croutons, crispy roasted chickpeas, or fresh herbs.
Butternut Squash and Leek Soup
Ingredients
- 4 pounds butternut squash (1 large squash)
- 2 leeks (about 1 pound)
- 2 tablespoon olive oil
- 1¼ teaspoon kosher salt, divided
- ¼ cup unsalted butter
- 3 cloves garlic, minced (about 1 tablespoon)
- 1 teaspoon dried thyme
- ½ teaspoon ground black pepper
- 3 cups vegetable broth
- 14 ounces coconut milk (1 can)
Instructions
Roast the Butternut Squash and Leeks
- Preheat the oven to 350 F. Line a baking sheet with parchment paper.
- Cut the butternut squash in half lengthwise (from the stem down to the bottom). Scoop out the seeds and discard. Place the halves cut-side-down on the baking sheet. Slice the white parts and tender green parts of the leeks into roughly one-inch chunks. Toss the leeks in a small bowl with the olive oil and ¼ teaspoon of the salt. Add the seasoned leeks to the baking sheet. (Discard the dark green parts of the leeks, or save them to make homemade vegetable stock.)
- Bake the butternut squash and leeks for about 40 to 50 minutes, until both are easily pierced with a fork all the way through.
- Let the squash cool for a few minutes, then scrape out the squash from the skin, and discard the skin.
Make the Soup
- Melt the butter in a large pot or Dutch oven on medium-low heat.
- Add the minced garlic and cook for 2 to 3 minutes, until it smells really fragrant and the garlic has softened.
- Add the baked squash and leeks along with the dried thyme, black pepper, remaining 1 teaspoon of salt, vegetable broth, and coconut milk. Bring to a boil on high heat, then reduce the heat to medium-low and simmer for 20 minutes.
- Either use an immersion blender to blend the soup right away. Or allow the soup to cool then work in batches to blend it in a high speed blender. If you blend hot soup in a blender, it’ll build up pressure and could cause the soup to explode! So either let your soup cool, or let it vent out the top, with a towel covering it to catch any splatters.
- To serve, ladle into bowls. Garnish with chives, roasted pumpkin seeds, more black pepper, a dollop of cream, croutons, or other herbs. Enjoy!!
Notes
- Roasting the squash and leeks first takes extra time, but trust me, the depth of flavor that comes from caramelizing the vegetables is so worth it!
- To add a kick of heat, add a quarter teaspoon of cayenne pepper or a half teaspoon of smoked paprika.
- If you don’t have leeks, you can substitute shallots or sweet onions. Watch them closely in the oven, as they may cook faster than the squash. Alternatively, you could sauté them in olive oil or butter on the stove.
- Instead of thyme, you could use rosemary or sage.
- If you don’t like coconut milk, replace it with an extra cup of broth. Note that your soup may not end up as creamy. You can also replace the coconut milk with heavy cream, if you don’t need your soup to be dairy free.
Mona
I did this for Christmas and the kids loved it, the butternut squash has a lovely cozy flavor
Carissa Erzen
Aww I'm so glad your kids loved it, that's so sweet to hear!