Ingreadient

• 1/4 pound (1 stick) unsalted butter
• 1 1/2 cups chopped yellow onion (2 onions)
• 1/4 cup flour
• 1 teaspoon kosher salt
• 1/2 teaspoon freshly ground black pepper
• defatted turkey drippings plus chicken stock to make 2 cups, heated
• 1 tablespoon cognac or brandy
• 1 tablespoon white wine, optional
• 1 tablespoon heavy cream, optional