The peppery flavor of watercress is complemented by the warming qualities of fresh ginger root. It brings a subtle Asian accent to this substantial soup, which can stand as supper when accompanied by chunks of bread.
3 tablespoons olive oil
6 large leeks, washed thoroughly and thinly sliced, white and pale green parts only
3 medium yellow onions, thinly sliced
3 cloves garlic, minced
1 2-inch knob of fresh ginger root, peeled and finely chopped
6 large potatoes, peeled and cut into 1-inch cubes
6-7 cups reduced-sodium chicken broth
3 bunches watercress, stems removed and coarsely chopped
1/2 cup whole milk
Kosher or sea salt and freshly ground black pepper, to taste
Pinch nutmeg
Garnish: sour cream or plain Greek-style yogurt
Garnish: sour cream or plain Greek-style yogurt
In a 4- to 5-quart heavy-bottomed pot, warm the olive oil over medium heat. Stir in the leeks and cook, stirring, until they start to soften, about 5 minutes. Stir in the onions and cook 3 more minutes. Add the garlic and ginger root and cook until all the vegetables are soft, 6 to 7 minutes longer.
Stir the potatoes into the leek/onion mixture, then add 6 cups of the broth. Raise heat to high and bring to a boil. Lower heat to medium-low and simmer, covered, until potatoes are tender, about 8 to 10 minutes. Add the watercress to the pot and simmer until the leaves are wilted, about 5 minutes.
Let cool slightly, then pur