I would a imagine a champaign breakfast would be a breakfast served in Champaign Illinois maybe? Although I doubt they have special breakfast offerings that no one has heard of. Maybe someone from Champaign can chime in?
If youre refering to a Champagne Breakfast, as in champagne the drink, its just like Mooncricket said; a breakfast of fruits and pastries served with champagne and OJ. And of course OJ and champgne makes a Mimosa (add the champagne to the OJ, so the champagne doesnt bubble over as much).
EDIT...and Mrs.ssippi beat me to it
