01 -
Melt the chocolate using a double boiler. Once it's fully melted, pour it into a bowl. Inflate six small balloons. Line a tray with parchment paper. Place six dollops of melted chocolate onto the tray. Dip the balloons into the melted chocolate, let the excess drip back into the bowl, and sit each balloon on a chocolate dollop. Let them dry for at least 4 hours, or preferably overnight.
02 -
Melt the chocolate and half the butter in a microwave or double boiler. Set it aside to cool. Combine the rest of the butter with the sugar until creamy. Separate the whites from the yolks. Mix the yolks with the butter-sugar mixture until smooth. Stir in the cooled chocolate and combine well. Beat the egg whites until stiff peaks form. Gradually fold three-quarters of the chocolate mixture into the whites with a spatula or wooden spoon to keep the mixture airy.
03 -
Spoon the mousse into the hardened chocolate shells. Using the remaining chocolate, swirl it on top of the mousse. Refrigerate for about 4 hours. Just before serving, top with a few chocolate eggs for decoration.