Cost per Serving:
Cook onion, celery, carrot and garlic in olive oil in a 4-quart saucepan over medium heat, stirring often, until tender, for about 6 minutes. Add potato and tomatoes, with their juice; add canful of water to pot. Bring mixture to a boil, reduce heat and simmer until potato is tender, for about 6 minutes.
Stir in clams, with their juice, and herbs and cook until heated through, for about 5 minutes.