Make a mousse:
Melt the chocolate and set aside.
Beat the sugar with the 50g of egg whites or 50g of cream until semi-assembled, and mix with the chocolate.
Chantilly:
Whip the 100g of heavy cream in a stiff peak and set aside.
Assemble your parfait in a cup, similar to the photo.
Mousse base, cracked biscuit, whipped cream... and so on.