Potato leek soup is one of the most simple homemade soups you can prepare. It comes together quickly with just a few simple ingredients. It’s total comfort food!
In a large, heavy bottom saucepan, heat the olive oil over medium-low heat. Keep a small cup of water nearby. Add the leeks along with a pinch of salt and cook, stirring, until they begin to soften. Turn the heat to medium and cook for 10 minutes, stirring occasionally. Whenever a brown glaze forms on the bottom of the pan, drizzle in around 1 tablespoon of water and scrape the brown bits into the leeks. You can turn the heat up or down as needed, but ideally you’ll deglaze the pan at least 3-4 times over the 10 minutes, which adds flavor to the soup. The leeks won’t be the color of caramelized onions after 10 minutes, just a light brown.
Add the potatoes, water and salt, then bring the soup to a boil. Reduce the heat to low, cover with the lid ajar to allow steam to escape, and simmer for 20-25 minutes, until the ingredients are tender. Puree with an immersion blender or food mill, then taste and adjust seasoning if needed.
Serve immediately, as is or topped with a dollop of sour cream and a sprinkle of fresh chives. Store leftovers in an airtight container in the refrigerator, and enjoy within 3-4 days.
Notes
Don’t use the darkest green part of the leeks. Discard them or save for homemade stock. Leeks are full of grit and need to be thoroughly washed before using. Here’s a good tutorial on how to clean leeks.
The original recipe skips the first step of caramelizing the leeks. The olive oil is omitted and the ingredients are simply added straight to the saucepan. This method makes a wonderful soup as well. Pureeing the soup is technically optional, but it’s how I prefer it.
For more flavor you can optionally replace half or all of the water with homemade vegetable or chicken stock. I wouldn’t recommend using store-bought broth in this recipe since there are so few ingredients.