Let egg whites warm to room temperature - about 1 hour.
Whip cream until very thick. Refrigerate until needed.
In top of double boiler over hot, not boiling,
water, melt chocolate, stirring constantly.
Whip egg whites until they peak. Gradually add confectioners' sugar and continue
beating until very stiff. Carefully fold egg whites into whipped cream. Very, very
slowly dribble melted chocolate into mixture, gently folding just enough to combine.
Carefully turn into an attractive serving dish.
Several hours before serving, decorate mousse with additional whipped cream which
has been sweetened and chocolate curls.
To make chocolate curls, warm chocolate bar in wrapper until slightly soft.
With vegetable peeler pressing lightly, pare along bar in a long, thin stroke.