Boil the celery and onion in 1/2 cup water in a large saucepan till the onion is soft.

Blend flour in 1/4 cup water till smooth.

Stir gradually into the onion mixture.

When smooth stir in remaining water.

Stir constantly till the mixture boils and thickens.

Reduce heat. Simmer covered for 5 minutes.

Stir in sour cream, cheese, parsley and lemon juice.

Serve hot with garlic rolls or croutons or just plain toasts.