I’ve always wanted to make a potato and leek soup. I know that might sound like a funny ambition, but there’s a backstory. In my twenties, I read the viral book Why French Women Don’t Get Fat (anyone else remember that one?). I even saw the author, Mireille Guiliano, on Oprah, and I was fascinated by the European mindset around food. At the time, my own relationship with food was far from healthy, and I was eager to find a better way. In the book, Guiliano shares her “magical leek soup,” a simple reset tool for weight loss. While her version didn’t include potatoes (and I’m not making it for that reason), it planted the seed in my mind that leeks could be the star of a soup.
Fast forward to now, as I’ve been adding more soups into my weekly rotation, I knew it was the perfect time to finally make my own. My twist: I swapped in white sweet potatoes instead of the usual white potatoes. They strike the perfect balance – subtly sweet yet creamy, without being overpowering. At first I was a little intimidated by leeks, having never cooked with them before, but they turned out to be surprisingly easy to prep. The result? A cozy, comforting bowl with a silky texture, the slight sweetness of white sweet potatoes, and the gentle onion-like flavor of leeks. It’s nourishing, delicious, and just right for busy weeknights.
Why You’ll Love This Soup
Simple, wholesome ingredients. Just a handful of pantry staples and fresh produce come together to make something so comforting.
Gut-friendly and nourishing. Made with white sweet potatoes and leeks, this soup is lower FODMAP, gentle on digestion, and packed with nutrients.
Creamy without cream. Full-fat coconut milk is blended in with the cooked potatoes and leeks to create a creamy texture without the dairy. It is optional, as the cooked potatoes alone creates a naturally velvety texture, so feel free to leave it out.
Perfect balance of flavors. The subtle sweetness of the white sweet potatoes pairs beautifully with the mild, onion-like flavor of leeks.
Cozy and versatile. Serve it as a light lunch, a side dish, or a hearty weeknight dinner with crusty bread or a protein on the side.
Quick and make-ahead friendly. This soup takes less than 45 minutes, and stores and reheats well, making it ideal for meal prep.
Tips, Variations & Substitutions
Choosing your potatoes. I love the subtle sweetness and creaminess of white sweet potatoes, but you can easily make this with orange sweet potatoes or regular white potatoes. Each one gives the soup a slightly different flavor profile.
Make it richer. If you can tolerate dairy, feel free to use full-fat cream instead of the coconut milk. You can also add a dollop of yogurt before serving.
Add protein. Keep it simple as a side, or make it a meal by adding shredded chicken, white beans, or lentils (if tolerated).
Season to taste. Leeks and potatoes are a blank canvas. I used dried thyme, but you can use fresh thyme or even rosemary or a bay leaf while simmering. From some extra healthy fats, drizzle your bowl with olive oil at the end.
Storage & reheating. This soup keeps well in the fridge for up to 4 days and can be frozen in portions. Reheat gently on the stovetop, thinning with a splash of broth or water if needed.
Make it chunkier. If you prefer more texture, only blend half of the soup and leave the rest as tender potato chunks with soft leeks.
Health Benefits of This White Sweet Potato & Leek Soup
White sweet potatoes. Ever since diagnosed with SIBO, I eat white sweet potatoes on repeat. They have been a simple, lower FODMAP substitution, and I have come to crave their subtle sweetness. They are rich in vitamin C, fiber, and complex carbs that provide steady energy without being overly starchy. Additionally, their mild sweetness also makes them easier to incorporate into savory dishes.
Leeks. Part of the allium family (like onions and garlic), leeks have a mild flavor and contain prebiotic fibers that help nourish a healthy gut microbiome. They also offer antioxidants that support overall wellness. Please know however, if you are intolerant to onions, leeks might not be for you.
Broth-based cooking. Using water or broth instead of oil keeps this soup light and easier to digest, while still allowing the flavors to shine. It’s a great option for those who want something warming, hydrating, and gut-friendly.
Naturally dairy-free. The creamy texture comes from blending coconut milk with the potatoes, so you get a velvety soup without needing cream or butter.
White Sweet Potato & Leek Soup
Equipment
- Large pot or Dutch Oven
- Hand immersion blender or blender
Ingredients
- 3 medium leeks white + light green parts only, sliced thin and rinsed well
- 2 pounds white sweet potatoes peeled and chopped into cubes (about 4-5 cups)
- 4 cups chicken or vegetable broth plus more as needed
- 1 teaspoon fresh thyme leaves or ½ teaspoon dried thyme
- Sea salt to taste
- Freshly ground black pepper if tolerated
- ½ cup full-fat coconut milk optional, for extra creaminess
- Chopped fresh chives or parsley, for garnish
Instructions
- In a large pot or Dutch oven, add ½ cup of broth and the sliced leeks. Simmer over medium high heat for 5–7 minutes until softened, stirring occasionally and adding more broth if needed.
- Add the potatoes, remaining broth, and thyme. Bring to a boil, then reduce heat to low and simmer for 20 minutes, or until the potatoes are very soft and fork tender.
- Add the coconut milk (if using) and use a hand immersion blender to puree the soup, or transfer to a blender and process until smooth. Season with sea salt to taste.
- Divide the soup into serving bowls and garnish with chopped chives or parsley if desired.
