Prepare the Sugar Syrup (see corresponding recipe below).
Whip the prepared Chocolate Butter Cream (see corresponding recipe below) to spreading consistency.
Place the cooled sheet of Chocolate Sponge Cake (see corresponding recipe below) on a sheet of parchment paper or plastic wrap.
Using a small pastry brush, evenly coat the sponge cake with the syrup.
Cover the sponge cake with a 3/8 inch layer of the Chocolate Butter Cream with the aid of a spatula.
Roll the cake over itself to form a roll. Wrap and refrigerate for at least one hour before assembling the Yule Log.
Remove the rolled cake from refrigerator. Slice off two ½ to ¾ inch sections from each end of the roll.
Frost the log completely with the Chocolate Butter Cream.
Place the 2 slices of cake onto the log approximately 2 inches from either end. Frost the top and the sides of the slices to form the look of cut branches.
Dip a fork into hot water, press lightly into the frosted log, and run the length of the log to form the look of bark. Decorate the “cut branches” and ends of the logs in a circular pattern to form “rings”.
Refrigerate cake. Decorate, as suggested below, just before serving.
Dust lightly with powdered sugar to give the impression of frost or snow, if desired.
Decorate the log with several Meringue Mushrooms. The mushrooms may be dusted with cocoa powder to achieve a more authentic look.
Combine the evaporated cane juice and water in a small sauce pan and boil over high heat.
Remove from the flame and allow to cool. Stir in the rum.
The syrup may be prepared in advanced and stored, covered, in the refrigerator.
Variation: Just about any liqueur or fruit juice may be mixed with the sugar syrup and used to moisten and flavor the sponge cake. Fruit and liqueur flavors may be mixed as well as matched.
Combine the whipping cream, sugar and 1 stick of butter in a heavy saucepan.
Place over high heat and bring to a boil, stirring occasionally. Remove from heat.
Beat the eggs in a glass or stainless steel bowl with a wire whisk. Slowly, pour the hot liquid into the beaten eggs, whisking constantly. Pour the mixture back into the saucepan and place over high heat. Return to a boil, stirring continually. Remove from the flame and transfer to the bowl of your electric mixer.
Whip on high speed for 5 minutes to aerate and cool the mixture. Reduce speed to low and add the remaining 3 sticks of slightly softened butter, 1 stick at a time, until completely blended.
Melt the chocolate in a small heavy saucepan, stirring often to prevent scorching. Remove from heat when completely melted and stir into the egg and sugar mixture. Add the vanilla and salt.
Resume whipping on high speed for another 7 to 10 minutes (until the frosting is fluffy and achieves a spreadable consistency). If after 10 minutes the frosting remains too liquid, chill for 5 to 10 minutes and rewhip.
Flavor the butter cream with 1 to 2 tablespoons of dark rum, if desired.
Butter cream keeps for 3 days in the refrigerator and 1 month in the freezer. Defrost in the refrigerator overnight and whip until fluffy when ready to use.
Preheat oven to 350 degrees.
Separate the eggs, making certain that none of the yolk mixes with the whites.
Sift the cornstarch, flour and powdered cocoa.
Whip the yolks and 1 cup of sugar at high speed for 5 minutes (until the mixture whitens and forms a ribbon).
Reduce the mixer speed to low and pour in the water and vanilla. Immediately fold in the cornstarch, flour and cocoa. Set aside.
Whip the egg whites with a pinch of salt in a separate bowl. Start at low speed; then increase speed as the whites begin to rise. Continue whipping while gradually adding the remaining 2⁄3 cup of sugar until the whites form soft peaks. (Do not over whip.)
Gently fold the yolk mixture into the whites with the aid of a rubber spatula. Pour the batter into a 3-inch deep, well-buttered and floured 10-inch cake pan.
Bake at 350 degrees for approximately 25 minutes. Test by inserting a skewer or toothpick into the cake. (The cake is done if the skewer comes out clean.)
Turn out the cake immediately and cool completely before using.