Buerre Noir Sauce 

1 cup balsamic vinegar

113 grams cold butter in cubes

1 tablespoon heavy cream

Pour vinegar into a sauce pan at medium heat. Simmer and reduce until the liquid is thick and coats the pan. Add the cold butter a cube at a time until the butter is all melted. Stir in the cream. The sauce should be thick and cover the back of the spoon. Serve on meat or scallops.