Smoked oyster sauce on beef tenderloin

We only have those lovely little beef filets when we get our quarterly meat supply from Blood Farm.  I happened to have smoked oysters on hand, so this is what I did:

Smoked Oyster Cream Sauce

1 T. butter
1 small shallot, finely chopped
1 T. chopped fresh sage,
3 T. vermouth or dry white wine
8 smoked oysters, with liquor
1/2 cup heavy cream
salt to taste

In a small saucepan, heat the butter over medium heat. Add the shallot and half the sage. Cook, stirring often, until the shallot is soft and just beginning to brown.

Add the vermouth and oyster liquor, and cook until it has almost all evaporated. Then add the oysters and cream and cook just until everything is heated through.

Put the whole shebang in the blender and puree until smooth. Put the sauce back in the pan to warm, and add the remaining sage and salt to taste.