Slow Cooker Leek and Potato Soup

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This slow cooker leek and potato soup recipe couldn’t be easier! Made with leeks, Yukon gold potatoes and heavy cream. Simply toss your ingredients into the slow cooker in the morning, and when you’re home, puree them for a delicious and creamy soup.

Serving of soup in a blue bowl on an orange napkin.

Leek and potato soup is my all-time favorite soup so it’s one that I make pretty regularly. Recently, I’ve been on the hunt for more slow cooker recipes that don’t require any hands-on cooking time, and I thought this soup was the perfect dish to reinvent for the slow cooker.

Why this recipe works

Simply toss all of the ingredients (except the cream) into the slow cooker and let it cook on low for eight hours. Because this is a pureed soup, you don’t need to worry about the texture of the vegetables as long as the potatoes and leeks are tender.

Ingredients on a board in separate bowls.

Ingredients you’ll need

  • Leeks are one of the key ingredients in this recipe, you’ll use the white and light green parts only. Be sure to clean the leeks well (see my tip below) as there can often be some dirt caught between the layers.
  • Potatoes I like to use Yukon gold (a great all-purpose potato) or white potatoes. These are less starchy than russet, so you’ll end up with a better soup texture.
  • For flavor I like to add dried thyme, garlic and a dried bay leaf.
  • Chili flakes are optional, but I find adding a little bit of heat to soup (I do this in my asparagus soup) helps to brighten up the flavor.
  • Butter adds richness to the soup, you could also use olive oil for this.
  • For the liquid I like to use chicken broth or vegetable broth. You could also use water, but you’ll want to adjust the amount of salt.
  • Cream is used to finish the soup and it helps to create a smooth and velvety texture. I like to use 35% cream but you could also use a lighter half and half (10% cream), or leave it out all together.
Grid of four photos showing steps for adding ingredients to a black slow cooker.

Step by step instructions

This soup could not be easier!

  1. In a slow cooker combine leeks, potatoes, garlic, butter, salt, dried thyme, chili flakes and the bay leaf. Cover with broth–either vegetable or chicken would work here. Cook on low for eight hours.
  2. After eight hours, your soup will be more muted in colour, remove the bay leaf and discard. In two batches, puree the soup in a blender and return it to the crockpot (or puree in the crockpot with an immersion blender). Stir in cream, if using, or a little bit of extra water.
Photo of soup in a blender and in the crock pot with cream being poured in.

Expert tips

  1. I find that the best way to clean the leeks is to slice them in half lengthwise and then thinly slice crosswise, toss them into a colander, rinse, and drain them a few times. You’ll want to swish and stir them around to make sure you loosen all of the dirt.
  2. I don’t peel the potatoes in this recipe, it saves time! If you want a lighter colored soup, you could peel them, but I don’t find it necessary.
  3. This soup will continue to thicken as it cools, if you want a runnier soup you can always stir in some more water, milk or cream to adjust to your preferences.
  4. If you’re in a time crunch, you can also cook this recipe in your crockpot on high for four hours.
Two servings of soup in blue bowls with an orange napkin.

Looking for more soup recipes?

This recipe was originally published on November 6, 2014 and updated on December 1, 2022 with a new crockpot version.

Closeup of soup in a blue bowl on an orange napkin.

Slow Cooker Leek and Potato Soup

Author: Louisa Clements