Potato and leek soup is a traditional Irish, wintertime, comfort food. It is a thick soup made of potatoes and leeks simmered with vegetable or chicken stock, and combined with heavy cream to create a comforting meal.
Served with buttered, brown soda bread, it is a delicious warm treat on a cold winter’s day.
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Classic Irish or French Soup Recipe
Classic potato leek soup is often considered to be a French recipe, but the Irish have been making this soup for centuries. I consider my potato leek soup recipe to be traditional Irish fare.
Some call it leek and potato soup, while others give the potatoes precedence when naming.
I had to go with the name potato and leek soup, since I think this is one of the very best potato soup recipes there is.
Using Potatoes to Make Soup
Leeks are also a favorite vegetable in Ireland. They add a subtle onion flavor to this soup, making it a satisfying meal on a cold and rainy days. And believe me, there are plenty cold, rainy days in Ireland, even in the summer.
Now you may prefer to make a plain potato soup without any leeks. I have a recipe for that one too. You’ll find my traditional Irish potato soup recipe here.
This recipe is for an Irish soup. Many credit the origins of this soup to France and not Ireland. There they create what is known as ‘vichyssoise’ which is usually served cold.
French leek and potato soup also consists of boiled and puréed leeks, onions, potatoes, cream, and chicken stock, but the big difference is in the serving temperature. The French serve their potato and leek soup chilled, unlike in Ireland where it is traditionally served steaming hot.
Cold soup just doesn’t cut it in Ireland, even in the summer. Who wants cold soup on a rainy day, and trust me, there are plenty rainy days during an Irish summer?
Irish Potato and Leek Soup Recipe
And so, let’s take a look at my Irish recipe for leek and potato soup.
This is one from my mother’s treasure trove of traditional Irish recipes.
At the end of this step-by-step photo tutorial you’ll find a printable recipe.
Ingredients for Potato and Leek Soup
Here’s a quick list of what you’ll need. Check out the recipe card at the bottom of the post where you’ll find exact quantities. You can toggle between US and Metric versions, plus you’ll also find all the nutritional information.
- thyme sprigs (fresh)
- bay leaves
- vegetable stock
- heavy whipping cream
- salt (or to taste)
- white pepper
- chopped chives (to garnish – optional)
- bacon bits (to garnish – optional)
Ingredient Tips and Substitutions
I included bacon and chives in the ingredient picture above, but these are completely optional and used only for garnish. Chopped green onion are also good as a garnish.
This soup can be vegetarian when vegetable stock is used. If you prefer chicken stock to add flavor yout your potato leek soup then feel free to substitute it for the vegetable stock.
I like to use russet potatoes for this recipe, but Yukon golds will also work just fine.
This soup is thickened by the potatoes so no flour is used. It’s naturally gluten-free as a result.
Once you master this basic recipe you can experiment with vegetable additions. Celery, kale or spinach can be chopped up and cooked alongside the leeks for a more nutritional profile.
For vegan potato leek soup be sure to use a vegan vegetable stock and substitute coconut milk for the heavy whipping cream. Also remember to use a vegan butter when sweating the vegetables.
Directions for Potato and Leek Soup
Let’s start with a little tutorial on how to clean and chop leeks.
Since these vegetable grow upwards through sandy soil, leek leaves can be full of grit and dirt.
Cleaning the leeks is extremely important if you don’t want gritty soup. We could give a whole new meaning to the southern term ‘grits’ by not washing the leeks well.
Chop the top and the bottoms off the leeks.
Here is a picture of the leeks I used.
Look how much dirt was between the top two layers. The dirt usually likes in the lower dark green parts of the leeks.
Cut the leeks in half, then chop each half into semicircles about ¼ inch thick.
Fill a big bowl of cold water and toss in the leeks. Use your fingers to separate the layers of each leek slice.
Keep parting the layers with your fingers and stirring the pieces in the water. Let the leeks stand in the water for about 5 minutes. The dirt will fall to the bottom of the bowl.
To drain the leeks lift them into a colander with your fingers. Do not pour the leeks and water into the colander since the settled dirt at the bottom of the bowl will just pour right over and redirty the leeks.
Run some clean water over the leeks in the colander to get rid of any dirt that might still be lingering.
Once drained, dry the leeks with some paper towels. They should be ready for cooking by now.
Peel and dice the potatoes.
Cut the potato into evenly sized cubes, about 2-inch pieces.
Chop the onion.
Don’t worry about getting the onion too small since the soup will be puréed after cooking.
Now we’re ready to cook.
Melt the butter in the bottom of a large soup pot.
I use salted butter, but if you wish to control how much sodium is added try an unsalted butter.
I like to use butter rather than oil, since it adds nice flavor and coats the vegetables well for cooking. Butter is more authentically Irish anyway.
Add the chopped leeks and potato to the pot.
Stir well to coat the surface of the vegetables with melted butter.
Turn the heat down to low.
Toss in the onion and mix well together.
Cover the pot and allow the vegetables to cook slowly, by ‘sweating’ for 15 minutes.
Every 3 minutes remove the lid and stir the vegetables to prevent sticking.
When the vegetables are beginning to soften, add the vegetable broth.
You can use all vegetable broth, or use 2 cups of water and 2 cups of broth. Chicken stock can also be used if you are not concerned about keeping the soup totally vegetarian.
Next add a the bay leaves and thyme sprigs. I use dried bay leaves, but for thyme I prefer fresh herbs.
These will be removed at the end of cooking.
Season the soup with white pepper. Black pepper will leave little specks in the soup when it is pureed, so white works much better.
The flavor of white pepper is more traditionally Irish also. Growing up in Ireland, we always kept white pepper in our pepper shaker for the kitchen table, not the typical black pepper of America.
Add salt if desired. I forgot to add salt in my ingredient picture above. I find store bought stocks are quite salty to begin with, so I sometimes skip adding salt.
Turn up the heat to bring the soup to simmering point. Once it starts to bubble, turn the heat to low and let it cook for another 20 to 25 minutes.
A slow simmer is better than a rolling boil for making soups. My soup making tips explain the reasons for simmering soups.
Once cooked, remove the thyme sprigs and bay leaves.
Purée the soup using an immersion blender.
If you don’t have one of these the soup can be transferred in batches to a blender, then blitzed.
Return the soup to the pot once it is smooth.
In years gone by, in the days before electric kitchen gadgets, this soup would be puréed by passing it through a sieve or strainer.
Add the heavy whipping cream and stir into the soup.
I use a half cup, but if you really like creamy soup, use up to 1 cup of cream.
Serve warm garnished with chopped chives and bacon bits if desired.
Irish brown bread is a perfect accompaniment to this creamy potato soup with a delicate onion flavor.
Recipe Card for Leek and Potato Soup
Here is the printable recipe card.
Potato and Leek Soup
- 2 large leeks
- 1¼ pounds potatoes 3 medium
- ½ large onion
- 1 ounce butter
- 2 thyme sprigs fresh
- 2 bay leaves
- 4 cups vegetable stock
- ½ cup heavy whipping cream
- ¼ teaspoon salt to taste
- ¼ teaspoon white pepper
- Chop the leeks. Wash them in a bowl of water, allowing the grit to fall to the bottom of the bowl. Lift the sliced leeks into a colander to drain. Rinse well and pat dry before using.
- Dice the potatoes and onion.
- Melt the butter in a large soup pot or dutch oven. Add the leeks, potatoes and onions, stirring to coat them in melted butter. Turn the heat to low. Cover the pot and allow the vegetables to 'sweat' for 15 minutes, stirring every 3 minutes to prevent burning.
- Add the vegetable broth, bay leaves, thyme sprigs, salt and pepper.
- Turn up the heat and bring to simmering point. Lower the heat and simmer for 20 to 25 minutes until vegetables are tender.
- Remove the bay leaves and thyme sprigs. Blend the soup until smooth with an immersion blender or in batches using a food processor or blender.
- Add the heavy whipping cream and stir into the soup. I use a half cup, but if you really like creamy soup, use up to 1 cup of cream.
- Serve hot in soup bowls. Garnish with bacon bits and chives if desired.
Nutrition Information is estimated based on the ingredients and cooking instructions as described in each recipe and is intended to be used for informational purposes only. Please note that nutrition details may vary based on methods of preparation, origin and freshness of ingredients used.
Wishing you all happy soup making days, especially during the fall and winter months.
You might like these other Irish inspired soups.
Thanks for following my recipes and ramblings.
Slán agus beannacht,
(Goodbye and blessings)
Irish American Mom
Here are some other recipes from Ireland you might enjoy…
For Pinterest fans, here’s a pin friendly image you might like to add to your boards.
And if you would like to check out more of my traditional Irish cooking, here’s a link to my recipe index.