There’s nothing quite like a big bowl of homemade soup on a cold day, and this slow cooker leek, fennel, and potato soup is one of my all-time favorites. It’s creamy, earthy, and packed with flavor thanks to the sweet leeks and tender potatoes, plus a bit of zing from fresh herbs on top.

Serve it up with some crusty bread, and it’s honestly the perfect cozy meal. It’s even better if you make it the day before, as the flavors get a chance to settle and blend. Each spoonful just tastes like pure comfort.

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Recipe Ingredients

For the Soup:

• 1/4 cup (60 ml) extra virgin olive oil
• 3 leeks (white part only), washed and thinly sliced
• 2 garlic cloves, coarsely chopped
• 1 fennel bulb, halved and thinly sliced
• 1 lb 12 oz (800 g) potatoes, cut into 1½-inch (4 cm) pieces
• 6 cups (1.5 liters) good-quality vegetable stock
• 1/3 cup (50 g) raw cashews
• 2 teaspoons fennel seeds, toasted and coarsely ground
• Sea salt and freshly ground black pepper, to taste
• Crusty bread, to serve

For the Herb Salsa:

• 1 large handful of flat-leaf parsley, coarsely chopped
• 3–4 tablespoons coarsely chopped mint
• 1 tablespoon finely snipped chives
• Finely grated zest of 1 lemon
• 1/3 cup (80 ml) extra virgin olive oil, plus extra for drizzling

How To Make Leek, Fennel and Potato Soup With Herb Salsa

1. Prepare the Ingredients: Pour the olive oil into a large slow cooker, then add the sliced leeks, garlic, fennel, potato pieces, and cashews. Season generously with sea salt, freshly ground black pepper, and ground fennel seeds.
2. Start Cooking: Set the slow cooker to high and cook for 5 hours, ensuring all the vegetables become very tender and the flavors meld together.
3. Prepare the Herb Salsa: When there are 10 minutes left for the soup to finish cooking, combine the parsley, mint, chives, lemon zest, and olive oil in a bowl. Stir well until the salsa ingredients are fully mixed.
4. Blend the Soup: Once the cooking time is up, use a stick blender, food processor, or blender to purée the soup in batches until it reaches a smooth, creamy consistency.
5. Adjust Seasoning: Taste the soup and adjust the salt and pepper if needed, making sure the flavors are balanced and the seasoning is just right.
6. Serve and Garnish: Ladle the soup into bowls, top with a generous spoonful of herb salsa, and drizzle with a little extra olive oil if desired. Serve with warm crusty bread on the side for dipping.

Recipe Tips

• Add a splash of coconut milk near the end of cooking to make the soup even creamier, adding a subtle richness that complements the fennel and leeks.
• For an extra layer of flavor, lightly caramelize the leeks and fennel in the olive oil before adding them to the slow cooker for a slightly sweet, deeper taste.
• If you prefer a heartier texture, blend only half the soup, leaving some chunks of potato and fennel to add variety in each spoonful.
• Swap out potatoes with sweet potatoes for a touch of natural sweetness, which pairs wonderfully with the herb salsa and adds extra creaminess.

Recipe FAQs and Variations

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