=== Lettuce Soup ===
(or, what to make when the lettuce in your garden is going insane)

**Ingredients**

  * 1 cup chopped onions, scallions, and/or shallots
  * 1 garlic clove, chopped
  * 3 tablespoons unsalted butter
  * 3/4 teaspoon ground coriander
  * 3/4 teaspoon salt
  * 1/4 teaspoon black pepper
  * 3/4 cup diced (1/3 inch) peeled potato (or any root vegetable. I used celeriac - YUM!)
  * 8 cups coarsely chopped lettuce leaves including ribs (3/4 lb)
  * 5-6 cups water or, better, broth

**Preparation**

Cook onion mixture and garlic in 2 tablespoons butter in a 4- to 5-quart heavy pot over moderately low heat, stirring, until softened, 3 to 5 minutes. 

Add coriander, salt, and pepper and cook, stirring, 1 minute. 

Stir in potato, lettuce, and water and bring to a boil, then reduce heat and simmer, covered, until potato is very tender, about 10 minutes.

Purée soup in batches in a blender (use caution when blending hot liquids) and transfer to a 2- to 3-quart saucepan. 

Bring soup to a simmer, then whisk in remaining tablespoon butter and salt and pepper to taste.