Ingredients:
1½ tablespoons safflower oil
2 medium leeks, trimmed, cleaned thoroughly and chopped (about 2 cups)
1 medium onion, sliced (about 1 cup)
1 teaspoon ground fennel seeds
1¼ pounds potatoes, coarsely cubed (about 3 cups)
3 cups chicken stock
1½ cups water
10 ounces arugula, washed, trimmed, to yield 4 cups
freshly ground pepper and sea salt to taste
Yogurt, 2 tablespoons per serving
4 arugula leaves finely slivered for garnish

Directions:

  1. Heat oil in a large pot. Add leeks, and onion; cook over moderately low heat, stirring often, until softened, about 10 minutes. Sprinkle with fennel and stir 30 seconds.
  2. Add potatoes, broth and water. Simmer 25 minutes, until soft. Add arugula and cook another 10 minutes longer, to until stems are soft. Add salt and pepper to taste.
  3. Puree to rough or smooth texture in a food processor or blender. Adjust seasoning. Serve hot or chilled topped with the yogurt and garnished with the arugula slivers.

Makes about 6 cups