Watercress and Potato Soup

Photo by Michael Piazza / Styled by Catrine Kelty

If you encounter different varieties of watercress while shopping, opt for the type with smaller, rounded, dark green leaves, stems that are thick toward the base (sometimes referred to as upland cress) with a distinctly sharp flavor.

Speaking of sharp, peppery flavor, the soup bears a distinct watercress flavor punch from the full two bunches in the ingredients. If you like a potent pep, use all the cress called for. If you prefer your soup a bit milder, dial back the cress to suit your taste.

The quantity of cream here is modest. Watercress and cream complement each other beautifully, but the soup isn’t meant to be overtly creamy; in fact, you can omit it if you wish as the potato blends into a dreamy, creamy purée.

Serves 4–6 (makes about 2 quarts)

3 tablespoons butter
1 large onion, chopped
1 large celery rib, chopped (about ¾ cup)
salt and freshly ground black pepper
2 medium garlic cloves, thinly sliced
1 quart water
2 cups homemade or packaged low-sodium chicken broth
1¼ pounds russet potatoes (about 2 medium-large), peeled and chopped (about 4¼ cups)
8 cups (packed) watercress leaves and small stems (thick stems removed; about 2 large bunches/6 ounces prepped), a few small sprigs reserved for garnish
1 tablespoon fresh lemon juice
¼–½ cup heavy cream

In a large saucepan over medium-high heat, melt the butter. Add the onion, celery and 1 teaspoon salt and cook, stirring, until the vegetables start to soften, about 4 minutes. Add the garlic and cook, stirring, until fragrant, about 40 seconds. Adjust the heat to medium-low, cover and continue cooking, stirring occasionally, until the vegetables have released their juices, about 8 minutes. Add the water, broth and potatoes, adjust heat to medium-high and bring to a boil. Reduce heat to very low, cover and simmer until the potatoes are very tender, about 20 minutes. Off heat, set aside to cool briefly, about 10 minutes.

Roughly chop the watercress, add it to the pot, stir and allow it to wilt for about 10 seconds. In a blender or with an immersion blender, purée mixture (working carefully and in batches if using a blender) until very smooth and uniform. Return the mixture to the pot if necessary, add the lemon juice, cream and pepper to taste, and heat over medium-low, stirring occasionally, until soup is heated through. Taste and adjust the seasoning with additional salt and pepper, if desired. Serve hot, at room temperature or chilled, garnishing each bowl with some of the reserved watercress.

Note: If serving chilled, you will certainly want to add more salt; cold food needs more seasoning!

This recipe appeared in the Spring 2020 issue as part of a larger story on Spring parties.