Slow Cooker Leek And Potato Soup

Name: Slow Cooker Leek And Potato Soup
Prep time: 10 min
Cook time: 240 min
Total time: 250 min
Ingredients: 45 g (3 tbs) butter; 30 g (2 tbs) olive oil; 2 leeks (sliced finely); 3 tsp minced garlic (or 3 cloves, crushed); 1.25 kg white potatoes (peeled and diced into small pieces); 1.5 litres liquid chicken stock; 2 dried bay leaves; salt and pepper (to season); 300 ml cream (or thin pouring cream); 2 tbs fresh chives (finely chopped, to serve)

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Introducing the easiest, most comforting and hearty Slow Cooker Leek and Potato Soup recipe ever!

It takes just 10 minutes to prepare... then set and forget and let the slow cooker prepare the creamiest, most delicious soup for you!

Serve with your favourite soft bread rolls, savoury muffins or ham and cheese scrolls.

A bowl of potato and leek soup with chopped chives sprinkled on top.

Just about all the work is done for you by using a slow cooker - with only 10 minutes to prep then let it cook by itself, ready in time for dinner!

Nourishing soups, such as this slow cooker potato and leek soup, are ideal for a simple mid-week family dinner or weekend lunch, served with plenty of crusty bread on the side.

And when winter vegetables are plentiful, soups make a healthy option that's budget friendly too... and great to stock up the freezer with meals made in advance.

Delicious carrot and lentil soup has been on the menu at my place lately, alternated with classic roast pumpkin soup, and of course, a family favourite, chicken, corn and noodle soup - always a winner!

Why You're Going To Love This Recipe

When you start to see leeks on sale in the supermarket, you know that winter's just around the corner......

Slow cooking is so easy! - there's very little preparation required, and once you assemble ingredients in the slow cooker there's nothing more to do - except come home later to the warm aroma of a comforting soup!
Inexpensive meal - with costs going up all over the place, it's helpful to be able to make an inexpensive, but tasty and healthy meal.
Great for left-overs - pack some for lunch the next day! Slow cooker potato and leek soup is freezer friendly too, and can be defrosted and reheated in the microwave or on the stove-top.
Seasonal - always best to use vegetables in season when they're at their best, in this case winter leeks - maybe you even grow your own?
Up your veggie intake - with a warm bowl of potato and leek soup. Leeks are full of antioxidants and Vitamin K, and potatoes are a great source of potassium, Vitamin C and Vitamin B6.

A spoonful of creamy potato soup held above a bowl.

What You Need

Leeks are known as the 'soup onion', and have a distinctive sweet flavour when cooked. Perfect for balancing this hearty potato soup!

Note: Scroll to the recipe card at the bottom for the ingredients quantities and full detailed method!

Butter and olive oil - for lightly sauteeing the leeks and garlic to develop the aromatic base of the soup.
Leeks - wash them well and finely slice. Use only the bottom white and light green parts as they are tender and full of flavour. Discard the base and the dark green leaves at the top of the leek.
Garlic - either crush fresh cloves, or do what I do for convenience by using store bought minced garlic.
Potatoes - peeled and diced. Choose a potato that's best for mashing such as sebago, desiree, pontiac, russet, dutch cream or yukon gold.
Chicken stock - for convenience I buy liquid chicken stock as its ready to go, however if you want to take the time, you can make your own chicken stock. Stock is made from simmering chicken bones, vegetables and herbs for several hours - it's the 'real thing' but very time consuming....see FAQs.
Bay leaves - traditionally used in soups, stews and casseroles to add a little more depth with their subtle herb and pepper flavours.
Salt and pepper - to taste.
Cream - preferably use a cooking cream or thin pouring cream as this won't curdle at higher temperatures. While I use a full-fat cream, you could use a light variety for a low fat option, or replace with evaporated milk or fresh 'light' milk for less fat.
Chives - fresh and chopped.

Equipment Required

Just three main items required for this slow cooker potato and leek soup:

Frying pan - to saute the sliced leeks and crushed garlic. Note: this is not required if your slow cooker can also be used to sear on a stove-top;
Slow cooker - also know as a crock pot;
Blender, food processor or Thermomix - to blend the soup.

An overhead shot of chives sprinkled on creamy soup in a bowl.

Step By Step Instructions

It's hard to know the true origin of potato and leek soup as 'rumours' include France, Ireland and Wales - three countries where potatoes were popular in the 18th century!

Note: Scroll to the recipe card at the bottom for the ingredients quantities and full detailed method!

Step 1 - Prepare Leeks And Saute

Wash your leeks well, and slice finely. See FAQs for how to prepare leeks.

In a frying pan over medium-low heat, heat the butter and olive oil. Add the leeks and garlic and cook for 5 minutes or until the leeks are translucent and soft.

Note: If you have a searing slow cooker, you can saute the leeks and garlic in the slow cooker on the stovetop - less dishes!

Leeks, garlic, butter and oil in a slow cooker.

Transfer sauteed leeks to your slow cooker/crock pot if a frying pan was used.

Leeks and garlic sauteing in a slow cooker.

Step 2 - Add Potatoes And Stock

Add the diced potatoes, liquid chicken stock and bay leaves.

Chunks of potato and liquid stock added to the crock pot.

Cook for 4 hours on HIGH or 8 hours on LOW (until the potatoes are falling apart).

At the end of the cooking time, you can remove the bay leaves and discard them.

Potato and leeks simmering in chicken stock.

Step 3 - Blend

Use a stick blender to puree the soup until smooth.

You can also use a food processor or Thermomix to puree the soup in batches, ensuring that it has cooled slightly before doing so.

Note: Be very careful at this stage as the soup can be hot!

Cream about to be poured into crock pot.

Step 4 - Add Cream And Chives

Stir through the cream and chives, and season with salt and pepper to taste.

Serve with an extra drizzle of cream and a sprinkle of extra chives (optional).

Creamy blended soup in a black slow cooker.

Expert Tips

For a vegetarian option - replace the chicken stock with vegetable stock.
Cream added at the end of cooking gives a silky richness and smooth creamy flavour.
You can use a cooking cream to reduce the chance of cream curdling, as a cooking cream can withstand higher temperatures.
Swap full fat cream for either a 'light' cream, evaporated milk or fresh milk for a lower fat option than full fat cream.
If using a hand held blender in the slow cooker, be careful of splashes as the soup will be hot!
If using a food processor or Thermomix to blend, do so in batches once the soup has cooled slightly to avoid steam build up and splashes.
If after blending, your soup is too thick - simply add an extra ½-1 cup of liquid chicken stock and stir through well.
Store potato and leek soup in an airtight container in the fridge for up to 3 days.
Freeze soup once it has cooled, in an airtight container for up to 3 months. Allow to defrost, then reheat in the microwave or on the stove top.

Savoury pinwheels behind a bowl of creamy soup in the foreground.

FAQs

How do I prepare leeks?

Leeks are grown in sandy soil that is piled up around them to keep the stem white, so it's important to wash them well. Firstly, rinse the leeks under running water to remove visible dirt or sand, and try to fan out the tops of the dark green leaves to allow the water to wash away any sandy soil further down the stem. Then cut off the root base and the tough dark green tops and discard - I keep only about 3-5cm of the green. Then place the washed stems in a bowl of water to loosen any further soil trapped, rinse again and drain leeks before slicing finely.

How do I make my own chicken stock?

You can make stock from raw chicken bones, cooked chicken carcasses, or a combination of both. Add vegetables such as celery, onion, carrots and herbs to the pot, then cover with water. Add salt and pepper to taste, then bring to the boil and reduce immediately to a simmer, allowing the stock to simmer for about 4 hours. Remove the bones and vegetables with a slotted spoon then strain the stock through a fine sieve. Chicken stock can be boiled rapidly for another hour to further reduce and intensify the flavour if you like.
Store in airtight containers in the fridge for up to a week, or up to 3 months in the freezer.

Does a slow cooker use a lot of power?

The simple answer is 'no'! On average, a slow cooker uses about the same amount of energy as a standard electric light bulb as it cooks at such a low temperature. So despite being on for a longer period of time, a slow cooker actually uses very little power.

A spoon resting in a bowl of creamy soup.

Serving Suggestions

I like to serve slow cooker potato and leek soup sprinkled with extra chopped chives, a drizzle of cream, and warm homemade foccacia or buttered soft bread rolls to soak up all the soup. However there's plenty of other options to try:

A dollop of sour cream and some crispy bacon sprinkled on top.
Crunchy bread croutons on top with a sprinkle of shaved parmesan.
A sprinkle of smoked paprika with a dollop of sour cream or greek yoghurt.
Baked Turkish bread or ciabatta.
Savoury muffins such as cheesy ham and corn muffins, or bacon and cheese muffins.
Savoury spinach and feta pinwheels or pizza scrolls.