Potato leek soup is spring's answer to winter's potato soup. With the arrival of warmer weather, switch from a heavier baked potato soup to a light and elegant potato leek soup. Mellow and mild, leeks are the unsung hero of spring.
The refined flavor of potatoes and leeks are often overshadowed by bacon and fennel, so here we've gone back to basics, simmering the classic combo all day in the slow cooker.
Often touted as "the soup onion," leeks usually play second fiddle in recipes for this classic soup. This potato leek soup is heavy on the leeks, with just enough potato to give the soup its signature creamy texture.
This is a recipe you can assemble in the slow cooker and leave for the whole day, coming home to the sweet, earthy, caramel perfume of long-cooked leeks and potato. There's no room for grittiness when it comes to potato leek soup, so the eight-hour cooking time guarantees the potatoes are tender.
To blend the soup before serving, an immersion blender is best. If you only have a traditional blender, use it but purée the hot ingredients in batches. A word of caution: Do not over-blend or mix on high speed, especially if using a high-powered blender, as the potato texture can turn gummy.
You can use the pre-frozen packs of sliced leeks or buy them whole. It just takes a few extra steps to trim and clean leeks, but they are steps you won't want to skip. Leeks grow in the soil, as do other onions. But unlike the yellow onion orbs, soil gets trapped between the leek layers. Simply trim away the root end and the dark green stalks. Slice the leek lengthwise and rinse under running water to dislodge any soil or grit. Then slice crosswise into half-moons before adding to the slow cooker.
More Recipes with Leeks
Slow Cooker Potato Leek Soup
Serves 4 to 6
Yukon gold potatoes, peeled and diced
sliced fresh or frozen leeks, white and light green parts only (from 4 leeks)
low-sodium vegetable broth
1 1/2 teaspoons
chopped fresh thyme leaves, plus extra for serving
freshly ground white or black pepper
sour cream, plus extra for serving
Place the potatoes, leeks, broth, butter, salt, thyme, and pepper in a 3- to 4-quart slow cooker and stir to combine. Cover and cook on the LOW setting until potatoes are very tender, about 8 hours.
Blend the soup with an immersion blender until smooth. (Alternatively, transfer the vegetables, in batches, to a stand blender. Blend on low speed until smooth. Return the blended soup to the slow cooker.) Add the sour cream and whisk to combine. Ladle into bowls and serve with an extra swirl of sour cream and a sprinkle of chopped fresh thyme.
Storage: Refrigerate leftovers for up to 4 days.