Wash and finely slice the leeks down to the root, adding them to a sieve once more to rinse well.Leeks can be very dirty, as sand/dirt gets stuck between the layers, so it’s important to wash them thoroughly after slicing away the tough dark green parts of the leek (which are very tough). Slicing it in half lengthwise to get between all the layers can help.
Peel and chop the potatoes into 1-inch pieces, transferring them to a bowl of water as you go. Mince the garlic.
Step 2: Sauté the Ingredients
Add butter and oil to a large, thick-bottomed saucepan or Dutch oven, and heat over medium heat until the butter has melted.
Once hot, add the leek, garlic, thyme, bay leaf, and some salt and pepper. Sauté for 2-3 minutes to soften the leek.If you want to add more flavor, sauté the leek for longer, until it starts to lightly brown/ caramelize, only adding the garlic in the last minute to avoid burning it.
Step 3: Leave it to Simmer
Add the potatoes and vegetable stock and bring the mixture to a boil. Then, reduce the heat to a simmer, cover with a lid, and cook for around 15-20 minutes, or until the potatoes are tender.
Remove the bay leaf.
Step 4: Blend the soup
Use an immersion blender (directly in the pan) or regular blender/food processor to carefully puree the potato soup until smooth and creamy or your desired consistency.When using a stand blender, make sure not to overfill the jug (work in batches), and use a clean kitchen towel to hold the lid down as you blend, pausing to lift it and allow steam to escape. If it has a chute, leave it open.
Once blended, add the cream to the soup and stir it in over low heat until thoroughly combined. Give the soup a last taste and adjust the seasonings to your liking. Serve and enjoy!
Store: Allow the soup to cool and then store it in an airtight container in the fridge for 4-5 days. It tastes even better on day two!Freeze: It's best to freeze this soup without the dairy. Freeze it within freezer-safe containers (with headspace) or Ziplock bags (with excess air squeezed out) for 3 months. Allow it to thaw overnight in the refrigerator before reheating, adding the dairy in right at the end to avoid curdling.Reheat: Use either the stovetop (over medium heat) or microwave (2-3 minutes, stirring halfway). If you're reheating soup with dairy, do so gently to avoid curdling. Add more stock if necessary.
To change the texture: If you’d prefer a chunky leek and potato soup, leave it entirely unblended or blend to your desired consistency. You could even leave the potato peels on when making it chunky.
Adjust the consistency: After blending the soup, add more stock for a thinner soup if desired.
To reduce oil/butter usage: Use vegetable stock to cook the veggies, though it won’t be as rich, and the vegetables won’t caramelize as much.
Serve in warm bowls: The soup will stay warm for longer. You can heat them in the microwave or oven.
Don’t add the dairy too soon: Otherwise, it can cause the soup to separate/curdle.
For more flavor: It's best to lightly caramelize the leeks for more flavor and depth.
Enjoy it warm or chilled: I’ll admit I don’t do much of the latter, but it is possible (called "Vichyssoise").
Optional Add-Ins & Recipe Variations:
Vegan version: use coconut cream or another dairy-free cream along with vegan butter.
Onion: You could use white or yellow onion to further the oniony flavor alongside the leek.
Kale/Spinach: A nutrient-dense addition to the soup without changing the flavor too much. Add kale a few minutes before everything is ready to give it time to soften. Spinach can be added right at the end.
Watercress: Turn this into potage un cresson with the addition of plenty of watercress.
Sage: To add along with the thyme.
Other vegetables: Diced carrots and celery both work within this soup.
White wine: Add about ¼ cup of dry white wine to the pot while the leeks sauté, allowing it to cook away before moving on to the next step.
Lemon juice: I love finishing creamy soups like this with a splash of fresh lemon juice for brightness and depth.
Parmesan rind: Adds depth and dissolves (somewhat) into the soup. Remove any remaining rind before blending.
Crockpot Potato Leek Soup: For soup that slowly cooks throughout the day, ready in time for dinner, try this slow cooker leek and potato soup.
Follow steps 1-2 above, sauteing the ingredients on the stovetop.
Then transfer those to a crockpot with the remaining ingredients (except the cream). Cook on LOW for 6-8 hours or HIGH for 4-5 hours, until the potatoes are tender.
Once ready, remove the bay leaf, blend with an immersion blender, and stir in the cream.
Add extra broth if it reduces too much while cooking. Once ready, use the ‘keep warm’ setting if you don't plan to enjoy it immediately.Instant Pot Potato Leek Soup: This Instant Pot leek and potato soup is ready in around 25 minutes from scratch with minimal effort!
Start by using the Instant Pot sauté function to sauté the leek and garlic until softened. Then add the potato and spices and continue to sauté until fragrant.
Then, add the remaining ingredients (except the cream), cover, and cook on MANUAL high pressure for 8 minutes.
Then carefully release the quick-release pressure valve and open the lid. Remove the bay leaf, then blend the soup with an immersion blender. Stir in the cream, then taste and adjust any seasonings. Enjoy!
Check the blog post for more tips, serving recommendations, and answers to top FAQs!