Cucumber soup with lemongrass and spinach

Ingredients

 * 2 tbsp unsalted butter
 * 2 ribs celery, strings removed
 * - with a vegetable peeler
 * - chopped
 * 1 small onion, minced
 * 2 stalks fresh lemongrass
 * - tender inside only, minced
 * 2 med cucumbers, peeled, seeded
 * - chopped
 * 2 cup chicken stock or broth
 * 1 1/2 cup spinach leaves
 * 1/4 cup fresh cilantro leaves
 * 3 tbsp whipping cream, if desired
 * salt, pepper to taste

Directions
Preparation time: 15 minutes. Cooking time: 25 minutes. Yield: 5 cups. Melt butter in a large saucepan. Add celery, onion and lemongrass. Cook gently until onion is tender, 15 minutes. Add cucumbers and stock. Heat to a boil; reduce heat, cover and simmer until cucumber is tender, 10 minutes. Strain solids from liquid, reserving both. Puree solids with spinach and cilantro in a blender or food processor. Add reserved liquid, cream, salt and pepper; mix until smooth. Serve warm or chilled