Lightly butter an 8 cup charlotte mold and line the bottom with wax paper to insure quick release.
Mix the kirsch with 1/2 cup cold water in a shallow dish. Working with one boudoir at a time (you don't want to leave them lying in the alcohol or they will disintegrate), quickly roll it in the alcohol and place it standing against the side of the charlotte pan with its curved side facing outward. Line the whole pan neatly in this fashion.
Separate the eggs. Place the egg whites in a mixing bowl and have the yolks ready to add to the chocolate mixture.
Using a double boiler, heat the chocolate and milk, blending until smooth with a wooden spoon (no need to boil the water in the double boiler for this - best just to keep it at a simmer). Add in the butter, one tablespoon at a time, blending until smooth after each addition. Add in the egg yolks one at a time, blending well after each. Beat the mixture for several minutes with the wooden spoon until smooth and glossy. Remove from the heat.
Beat the egg whites until stiff and then beat in the powdered sugar.
In another bowl beat the chilled cream until it forms soft peaks (you don't want this too stiff or it is hard to blend in to the other ingredients).
Blend the chocolate mixture into the whipped cream and than fold in the egg whites. You want to end up with everything completely blended but a light hand is needed to keep things fluffy.
Pour the mousse into the prepared charlotte pan pushing on it sightly to make sure it fills the pan completely. Line the top of the pan with more boudoirs that have been briefly soaked in the kirsch mixture. You may want to add two layers of boudoirs to create a firm foundation for your chocolate mousse when you turn it over.
Cover the cake with plastic wrap and place a weight on top of it (I use a pan that is just the size of the charlotte pan and put a heavy can of beans on top). Place in the refrigerator over night.
To serve, simply remove the plastic wrap and invert the charlotte on a serving plate. It should slide right out. Decorate as you wish - whipped cream, cherries, shaved chocolate - or just serve as is.