1 cup French Tomato Sauce
2 tablespoons Balsamic vinegar
1 tablespoon Chopped shallots
1 tablespoon Chopped parsley
1/2 pound Cold butter, cubed into 1″ pieces
Salt, to taste
Freshly-ground black pepper, to taste
In a small nonreactive saucepan, heat the tomato sauce, vinegar, and shallots until they form a thick paste, measuring about 1/4 cup. Now slowly whisk in the cold butter, a few cubes at a time into the reduced sauce. Make sure to completely incorporate each addition of butter before adding any more. Once all the butter is incorporated, stir in the parsley and adjust the seasonings. Serve on top of potato pancakes, fish, or chicken.
This recipe yields just over 1 cup of butter.