Combine 2 tablespoons sugar with 2 tablespoons vinegar. Boil and caramelize. Add Demi-glace.

Remove zest from an orange and a lemon. Cut into julienne strips. Put them into cold water. Bring to a boil, thus blanching them to remove their bitterness. Lift from water and add to sauce. Stir in 2 tablespoons frozen orange juice and 1 teaspoon lemon juice. Simmer 10 minutes.

Finish with Cognac and Madeira from Demi-glace recipe and 2 tablespoons Grand Marnier. Adjust seasonings and thickness of sauce with beurre manié. For fowl.