Melt the chocolate in the top of a double boiler. Do not cook the chocolate. This should be done SLOWLY over minimum heat.
Boil the cream. Once the chocolate is completely melted, and the cream just boiled, combine in the top of the double boiler.
Take off the top pan from the water, and (off heat) mix until completely combined. Keep stirring until it is relatively cool. Allow to sit until it is cool enough to put into a refrigerator.
Refrigerate overnight (NO SHORT CUTS HERE!!!).
The next morning, melt this wonderful mixture again in a double boiler. When it is completely melted again, mix in the butter until it is completely absorbed. Whip, either with a hand whisk or a very slow electric gizmo, until the butter is completely absorbed and the mixture is cool again. This can take an hour or longer, depending upon the chocolate, etc. Let cool, and refrigerate overnight once more (this is not as critical as the first cooling; a few hours will be enough).
Heat once again, and whip until cool. Refrigerate until it is thick enough to pipe through a pastry bag. Using a half-inch ozzle, make little balls on a big piece of parchment paper that has cocoa powder spread on it. Roll in the powder. Keep chilled until just before serving. Let them return to just above room temperature before eating.
Combine sugar, condensed milk, butter, salt, chocolate, and corn syrup in a HEAVY 3-quart saucepan. Heat slowly.
Stir until everything is melted. When the chocolate is melted thoroughly, beat with electric mixer (I ain't proud!) until smooth.
Let cook to halfway between soft and medium ball stage (use candy thermometer if available)
Let cool until barely touchable. (due to heat)
Stir in chopped walnuts, vanilla, and rum. Beat the mixture until it starts to set.
When it starts to set, get it into an 8-inch square pan. (buttered, of course) If you wait to do this, you will eat it out of the saucepan.
CHOCOLATE MOUSSE
INGREDIENTS (Serves 12-20)
CRUST
1/2 cup butter
1 cup flour
1 egg yolk (see note)
1 tsp vanilla
1 tsp grated lemon peel (optional)
FILLING
13 oz semisweet chocolate (see note)
3 oz unsweetened chocolate
2 whole eggs
4 eggs, separated
16 oz whipping cream
powdered (confectioner's) sugar
PROCEDURE
Make the crust: Preheat oven to 350 deg. F. Cut flour and butter together. With a fork mix in egg yolk, vanilla, and lemon peel. Press onto the bottom and sides of a 9 inch springform pan, and bake for 10-12 minutes at 350 deg. F, or until it just begins to turn slightly golden.
Melt all the chocolate in a double boiler.
Whip the whipping cream with 2-3 Tbsp of powdered sugar (the stiffer you whip it, the stiffer the mousse will be).
Beat the eggs whites with 2-3 Tbsp powdered sugar.
Remove the top pan of the double boiler (with the melted chocolate) from the bottom pan and let it cool a bit. ("Cool" means it's only cool enough so that when you add the eggs in the next step, they don't cook. You still need to be able to stir it.)
Add the whole eggs to the chocolate, one at a time, and mix well.
Then add the egg yolks one at a time and mix well.
Mix some of the whipping cream (enough to lighten the chocolate) into the chocolate.
Alternately fold in the whipping cream and the egg whites into the chocolate.