To prepare stock, melt 3 tablespoons butter in a 3-quart stockpot. Skim off foam. Add carrots, onion, celery and crushed peppercorns. Sauté until vegetables soften. Stir in wine, fish stock and bay leaf. Bring mixture to a boil. Scrub clams. Add to pot. Cover; simmer for about 10 minutes or until clams open.
Remove clams from pot with a slotted spoon. Pull out meat from clams. Chop meat; set aside or refrigerate until ready to use.
Strain stock; set aside or refrigerate until ready to use.
To prepare chowder: In another 3-quart stockpot, melt 6 tablespoons butter. Add celery, onion and potato. Sauté until vegetables soften. Stir in clam stock, garlic, thyme, bay leaf, and salt and pepper to taste. Add chopped clam meat. Cook over medium heat for 20 to 25 minutes, or until vegetables are tender.
In a separate saucepan, melt remaining 4 tablespoons butter. Gradually stir in flour to form a light paste, or roux. Remove from heat. Gradually whisk roux into chowder. Let simmer for about 10 minutes or until the mixture begins to thicken.
Remove from heat. Stir in cream.Makes 12 to 16 Source: