Chocolate Genoise Roll:
3 large eggs
3 large egg yolks
Pinch of salt
3/4 cup sugar
1/3 cup cake flour
1/3 cup cornstarch
1/4 cup Valrhona cocoa powder

Line jelly-roll pan with parchment paper. Butter the paper and dust thin layer of flower on butter. Set rack in the middle of the oven and preheat to 400 degrees. Half-fill a medium saucepan with water and bring it to a boil over high heat. Lower the heat so the water is simmering. Whisk the eggs, yolks, salt, and sugar together in the bowl of a heavy-duty mixer. Place over the pan of simmering water and whisk gently until the mixture is just lukewarm. Attach the bowl to the mixer and with the whisk attachment, whip on medium-high speed until the egg mixture is cooled and tripled in volume. While the eggs are whipping, stir together the flour, cornstarch, and cocoa. Sift 1/3 of the flour mixture over the beaten eggs. Use a rubber spatula to fold in the flour mixture, making sure to scrape all the way to the bottom of the bowl on every pass through the batter to prevent the flour mixture from accumulating there and making lumps. Repeat with another 1/3 of the flour mixture and finally with the remainder. Scrape the batter into the prepared pan and smooth the top.

Bake the genoise for about 9 to 10 minutes, or until well risen, deep and firm to the touch. (Make sure the cake doesn't overbake as it will make it hard to roll.) If necessary, use a small paring knife to loosen the cake from the sides of the pan. Spread kitchen cloth on working surface and sprinkle with sugar. Invert the cake onto the kitchen cloth and let the cake cool right side up for a minute. Remove the paper and immediately roll into a log.

 

Chocolate Ganache Icing:
4 ounces bittersweet chocolate
2/3 cup heavy cream

Chop chocolate into small pieces and place in a medium bowl. Heat cream on stove until bubbles begin to appear around the edges (don't boil) and pour over the chocolate. Let stand for 5 minutes and stir until smooth. Refridgerate until coldbut not solid, stirring occasionally.

 

Cream Filling:
2 cups heavy cream
1 teaspoon Cognac
sugar or vanilla sugar to taste
some of the chocolate ganache from the icing

 

Decorations:
Marzipan Mushrooms: Roll half of the m arzipan into balls for the caps and half into cylindrical lenghts for the stems.
Holly leaves: Knead greed color into marzipan and use cutter to cut out leaves.
Holly berries: Knead red color into a tiny piece of marzipan. Roll into tiny balls.
Pine cones: Knead chocolate into marzipan. Form cone shape and use scissors to slash sides of the cones.