The broth was simply milk, oyster liquor, peppercorns and a few sprigs of parsley.

Open the oysters, reserve the oyster liquor and strain it to remove any portions of shell or sand.

Add the reserved oyster liquor to the pan with the cream.

Mix flour with enough of the reserved oyster liquor to make a paste.

Add the oyster liquor, bay leaves and thyme sprigs and let simmer about 35 minutes.

Return the mixture to the saucepan and stir in the reserved oyster liquor.

Blend cornstarch with a little of the oyster liquor to make smooth paste.

Reduce the heat to medium-low and stir in the reserved oyster liquor.

Open the oysters, leaving them on the half shell, and reserve the oyster liquor.

Add the oyster liquor, stirring vigorously with the whisk.