Watercress Soup

Clean the watercress well in a couple of changes of cold water to make sure there’s no grit. You can use all the leaves and tender stems, but any stems that feel especially tough and woody, don’t use. I added peas to give it some extra body and to bolster the color, but you can leave them out if you wish. If you want a creamier soup, blend a few tablespoons of heavy cream or creme fraiche into the soup in step 3. You can garnish this soup in any number of ways, a few I mentioned in the post – from a spoonful of yogurt or cream swirled over the top with fresh herbs, to a handful of seeds or bits of crumbled bacon strewn over the top. It’s your call.

3 tablespoons butter
1 medium onion, peeled and diced
salt and freshly ground black pepper
6 cups (1.5L) water
1 pound (450g) potatoes, peeled and diced
8 ounces (225g, about 9 cups) watercress leaves and tender stems
1 cup (150g) fresh or frozen peas

In a Dutch oven or soup pot, melt the butter. Add the onion, season with salt and pepper, and cook over medium heat, stirring frequently until the onion is translucent, about 5 to 6 minutes. Add the water and diced potato and cook, partially covered, until the potato cubes are tender, about 10 minutes. When poked with a paring knife, the knife should meet no resistance.
Turn off the heat and add the watercress and peas, stirring a few times to wilt the cress.
Puree the soup using an immersion blender, or wait until the soup is lukewarm and puree until smooth in a blender. (Pureeing hot soup in a traditional blender will cause it to overflow, so wait until the soup is tepid.)
Once the soup is pureed, rewarm the soup in the pot, season with salt and pepper, and serve.

Notes

Storage: The soup will keep for up to three or four days in the refrigerator. It can be frozen for up to two months.