This tasty and delicious Slow Cooker Leek and Potato Soup recipe is 100% going to be your go-to recipe for cosy winter nights. Caramelising the leeks in butter, before adding the potatoes, milk and stock, will deepen the flavour. And most importantly, it will keep you coming back for more!
A touch of double cream adds a subtle richness alongside the creamy, thick texture achieved by the blended potatoes.
Soup season is one of my favourite seasons. The joy of living in Scotland means that I’m not confined to eating this only during Winter time. And if, like me, superior flavour and taste is important to you then this soup ticks all the boxes. If the Slow Cooker is your best friend due to being short on time, then this is the soup recipe for you!
Leek and Potato Soup can be a very hit or miss experience for me; so this recipe was born following regular disappointment when eating out. Honestly, my thought was, “it must be able to taste better than this”. And let me tell you, it can and it does!
Why Caramelise The Leeks First?
Caramelising the leeks, much like you would caramelise onions for French Onion soup, adds a sweet, delicious nutty taste to the soup.
If you don’t have time to caramelise the leeks, you can add all the ingredients in at the start and cook on High for 4 hours or Low for 8 hours and then blend up as per method. But note that you won’t get the same depth of flavour compared to if you’d followed the caramelisation step.
This part is really what makes this Leek and Potato soup stand out from all the rest, especially as the part that matters is all done for you by the Slow Cooker!
Why I Love It
Simple, easy, chuck-it-all-in-a-pot Slow Cooker Leek and Potato Soup in the Slow Cooker is the perfect option for hands-off cooking when you don’t have time to stand over a hob watching vegetables caramelise.
It’s creamy, rich, thick and so delightfully decadent that you’ll wonder how it’s less than 400kcal per portion!
The texture is quite unlike any other Leek and Potato soup I’ve had before, and I hope you love it too. Let me know what you think by leaving a comment below.
Suitable For The Whole Family
I feel comfortable giving this to my children who follow Baby Led Weaning (BLW)
Suitable from around 6 months old.
The only element I would modify is the salt content:
Reduce or remove the amount of salt by using reduced salt stock cubes, unsalted butter and season any adult portions after the soup has been blitzed up or after you’ve served.
I serve the soup with cubes of bread that have been soaked in it so that they can lift up pieces of bread coated in the soup with their own hands.
Ingredients + Substitutions For Slow Cooker Leek and Potato Soup
Butter: I use salted butter as this adds additional seasoning but use unsalted if you prefer or you’re trying to keep salt content low for young kids (you can always add more salt at the end)
Onion
Leeks
Sugar: any sugar will be suitable (caster, granulated, golden etc.)
Garlic: I always opt for fresh garlic but you can use 1 teaspoon of garlic paste if easier
Potatoes: I use Maris Piper variety usually, but any type of potato will be suitable
Chicken Broth: chicken bone broth from Borough Broth Company (use code LAUREN15 for 15% off) is what I usually use, or chicken stock. You can swap for Vegetable Stock if you want to make the recipe vegetarian.
Milk: I like using whole milk as it adds a richness in flavour, but swap for a lower fat option to reduce calories
Double Cream: you could use single cream if you want to reduce calories
Salt
How To Make Slow Cooker Leek and Potato Soup
Place butter, leeks and onion in your slow cooker.
Then add garlic & sugar to slow cooker. Cook on High for 4-6 hours or Low for 8-10 hours (ideally stir a handful of times throughout).
Add chopped potatoes, chicken bone broth and milk – cook on High for 4 hours or Low for 8 hours.
Pour in double cream then blitz up in food processor / blender or use a hand blender until its totally smooth
Finally, season with salt (use less or more to taste but this is what suited me) and serve.
Can I Make This Soup Without A Slow Cooker?
Yes you can! Please see my hob method below:
1. Add butter, leeks, onion, garlic & sugar to large pot and cook on medium heat for approx 1 hour (until leeks are caramelised), stirring occasionally.
2. Add potatoes, bone broth/stock and milk – simmer on low/medium heat for approx 90 mins (until potatoes are soft). You don’t want to cook on too high a heat as the milk might curdle, hence low & slow!
3. Add double cream, then blitz with hand blender or in food processor.
4. Season with salt & pepper then serve.
FAQs
You absolutely can! Just add everything (except the cream) into the slow cooker and cook on High for 4 hours or Low for 8 hours and then blend up as per method.
Yes – use plant based butter, milk and cream.
Storage
How long does it keep in the fridge – approx. 4-5 days as long as your fridge is below 4C
Can you freeze it – the soup can be frozen for up to 3 months. The exact duration will be dictated by what temperature your freezer is and also where in the freezer you store it.
What type of container can you freeze soup in? When freezing soup, you can use any freezer safe container – made of plastic, glass or freezer-safe bags (as this is also a good space saver).
And finally…
If you do choose to make it, I hope you enjoy it!
Why not try some of my other soup recipes like my One Tray Tomato and Basil Soup or Carrot and Coriander with Thai influences?
If you have any questions, or want to tell me what you think of my recipe, then please leave a comment below!
Slow Cooker Leek And Potato Soup
Ingredients
- 120 g salted butter
- 1 onion large
- 500 g leeks dark green parts removed then chopped
- 1 tsp sugar
- 3 cloves garlic
- 800 g potatoes peeled & chopped
- 750 ml chicken bone broth or chicken stock
- 750 ml whole milk
- 150 ml double cream heavy cream
- 1 ½ tsp salt
Instructions
- Place 120 g salted butter, 500 g leeks, 1 onion, 3 cloves garlic & 1 tsp sugar in your slow cooker – cook on High for 4-6 hours or Low for 8-10 hours (ideally stir a handful of times throughout)
- Add 800 g potatoes, 750 ml chicken bone broth(or chicken stock) and 750 ml whole milk – cook on High for 4 hours or Low for 8 hours.
- Pour in 150 ml double cream then blitz up in food processor / blender or use a hand blender until its totally smooth
- Finally, season with 1 1/2 tsp salt (use less or more to taste but this is what suited me) and serve
3 responses
This soup is fabulous. I was also not a fan of leek and potato until I tried this in the slow cooker. And so easy to make and freeze. Perfect for dinner parties
thanks so much Janice – so happy you loved it!
Fabulous recipe and so easy. Great for a dinner party