For a super-colorful soup, sprinkle a capsule of powdered vitamin C into this soup when you puree it. The vitamin C helps the watercress keep its vibrant green color. If you’re dairy-intolerant, skip the milk and use stock or water, and garnish with frizzled shallots instead of sour cream. This can be made the day before. Reheat slowly. Serves 6.
Ingredients
2 tablespoons olive oil
1 large yellow onion, minced
2 medium russet potatoes, diced
Salt and pepper to taste
2 cups milk
3 cups vegetable stock
2 bunches fresh watercress, stalks and roots removed
6 tablespoons sour cream
Directions
Heat olive oil in a large saucepan over medium heat. Stir in onion, potato, a pinch of salt and a grind of pepper. Cook 10 minutes, until soft. Do not brown.
Add the stock and milk. Bring soup to a low simmer, cover and cook until potatoes are soft, about 20 minutes. Turn off heat, stir in watercress and cover. Let steep 5 minutes.
Puree soup in blender, working in batches to avoid explosions. Serve warm with a dollop of sour cream and a drizzle of olive oil.
