Place the sugar and red wine vinegar in a custard cup.
Cook on the highest setting for 2 minutes, until the sugar has caramelized.
Place to one side.
Put the giblets, onion, and chicken broth in a 4 cup glass measuring cup and cook in the microwave oven for 15 minutes at "sim mer" setting.
Strain 1/4 cup of the liquid into the container with the caramelized sugar and return to the measuring cup.
Cut the orange rind into tiny strips, half the length of a matchstick and as thin as possible.
Squeeze the orange.
Place the orange rind and juice in a custard cup in the microwave oven for 2 minutes on the highest setting.
Add to the strained liquid.
Add the Grand Marnier, and Madeira or brandy.
Season the" sauce with salt and pepper.
Re turn to the oven for 2 minutes.
Stir in the cornstarch dissolved in cold water and cook 1 minute, until the sauce is thick and bub bling hot.