FRIDAY NIGHT DINNER-- cream of tomato soup

This tomato soup recipe belonged to James Beard's mother.  Please try and use San Marzano tomatoes.  They make such a difference .

             JAMES BEARD's MOTHER'S CREAM of TOMATO SOUP

1 28-ounce can San Marzano tomatoes, undrained
1 cup beef broth
1 small onion, stuck with 4 to 5 cloves
1 teaspoon salt
1 teaspoon dried basil
1/4 to 1/2 teaspoon pepper
1/4 teaspoon bicarbonate of soda
1 1/2 tablespoon flour
1 1/2 tablespoon unsalted butter at room temperature
1 1/2 teaspoon sugar
1 cup half & half
1 cup whipping cream

Cook tomatoes, broth and seasonings in a covered saucepan 30 minutes over low heat.  Strain well through a fine sieve, pressing on the solids.  Add the soda and correct the seasonings.  Blend flour and butter together until a smooth paste.  Stir it along with the sugar into the tomato mixture and cook over medium heat until slightly thickened.  Add the cream to the tomato mixture very slowly, off the flame to prevent curdling.  Return to heat and bring soup very slowly almost to the boil.  Serve with homemade croutons.