My family has been making this cake for years around the holidays. It's probably the most festive cake I've ever eaten, let alone seen. What's great about it is, even though it looks heavy, both the cake and the filling are very light and airy, making this a great recipe for the days proceeding holiday munching! Enjoy.
For the log:
1/4 cup flour
1/3 cup cocoa powder
3/4 cup sugar
1/4 cup sifted confectioner's sugar
2/3 teaspoon baking powder
1/4 teaspoon salt
5 eggs, separated
1 teaspoon vanilla
2 tablespoons water
For the filling:
1 cup heavy cream
1 teaspoon vanilla
2 tablespoons confectioner's sugar
For the frosting:
1/2 cup butter, softened
1 1/2 cups confectioner's sugar
1/4 cup heavy cream
3 ounces unsweetened chocolate, melted
Preheat the oven to 375°F. Grease a jelly-roll pan, then line it with parchment paper and grease again. Set aside. In a large bowl, sift together the flour, cocoa, baking powder, and salt. In a medium bowl, beat the egg yolks and 1/2 cup of the granulated sugar until creamy. Add the vanilla and water and mix well.
In a separate bowl, with CLEAN beaters, beat the egg whites until fluffy. Add the remaining 1/4 cup granulated sugar and beat until stiff, glossy peaks form.
Add the flour mixture to the egg yolk mixture in batches, folding in between. Then, very carefully fold in the egg whites until blended. Pour the batter onto the jelly-roll pan and spread evenly to the edges. Bake for about 12 minutes, or until a knife comes out clean when inserted into the cake. Be careful not to overbake this cake!
While the cake is baking, lay a clean dish towel on a flat surface and dust it with the 1/4 cup of confectioner's sugar. When the cake is done, loosen the edges of the cake and quickly turn it over onto the towel. Remove the parchment paper. To keep the cake from setting into a flat shape, roll up the cake in the towel starting on the long ends and place on cooling rack until cooled.
For the filling, beat the heavy cream, vanilla, and confectioner's sugar together until a thick whipped cream forms. When the cake is cooled, carefully unroll it and spread the whipped filling evenly over one side of the cake (the side that curls inwards), spreading to the edges. Roll the cake up again to form a log, this time without the towel!
For the frosting, beat the butter, confectioner's sugar, cream, and melted chocolate until well-blended, adding more cream if necessary to thin the consistency. Using a serrated knife, carefully cut through the cake on an angle to form the second log piece. Attach to the main log using frosting. Cut off the remaining angled piece from the main log and do what you like with it (snack, anyone?). Frost the entire rolled cake with the frosting, using a fork to create shallow bark-like grooves.
At this point I went outside into the frigid cold and found a holly bush, where I hastily picked out holly leaves to decorate with. Then I went to a pine tree. Then I ran back inside and finished my decorations in the warm kitchen. Jolly!
Recipe from the December/January 1995 issue of Parenting.