1in a large saucepan, saute chopped onion in butter. Stir in flour slowly and cook, stirring constantly, just until bubbly. Stir in clams with liquid and clam juice.Continue cooking and stirring until mixture thickens and boils for one minute. Cover, reduce heat, and simmer 15 minutes to blend flavors. Blend in cream, tomato paste and lemon juice (if using). Heat slowly until hot.
liquid and clam