Melt butter over medium-low heat in a large sauté pan. Add onions and cook for 12 to 15 minutes, until the onions are lightly browned. Don't rush this step; it makes all the difference when the onions are well cooked.

Sprinkle the flour into the pan, whisk in. Add salt and pepper. Cook for 2 to 3 minutes. Add the hot chicken broth and Cognac. Cook uncovered for 4 to 5 minutes, stirring occasionally, until thickened. Add the cream. Yield: 3 cups.