Preheat the oven to 325 degrees F. Butter a rimmed jelly roll/baking sheet and line with parchment paper. Butter the top of the paper as well, especially the corners.
In a stand mixer with the whisk attachment, beat the egg yolks and granulated sugar on medium speed until fluffy and the sugar is not gritty, 10 to12 minutes.
While the eggs are beating, put the chocolate in a bowl and melt over a double boiler. When the chocolate is melted, remove from the heat and let it cool a bit. Sit the bowl in some cool water for a few minutes if necessary.
Incorporate the egg mixture into the chocolate by adding a little at a time to temper the mixture, so you don't cook the eggs. Add the espresso and 1 teaspoon vanilla extract.
In a clean bowl, with the whisk attachment, beat the egg whites until stiff peaks form. Incorporate one-quarter of the egg whites into the chocolate mixture; make sure no white streaks remain. Carefully fold in the remaining whites into the chocolate, taking care not to deflate the whites but making sure not to have any white streaks in the batter.
Spread the batter in the prepared pan and bake, 10 to 12 minutes. Remove from the oven and spread a dampened tea towel or several dampened paper towels over the top of the cake and let it sit for 30 minutes.
In a clean bowl, with the whisk attachment, whip the heavy cream, confectioners' sugar, bourbon, vanilla bean and the remaining 1 teaspoon vanilla extract on medium speed until stiff peaks form.
Carefully turn the cake out onto clean parchment paper, making sure to have 4 to 5 inches of excess paper at the end to help you roll the cake. Using a fine sieve or sifter, sprinkle 1/2 cup cocoa powder over the top of the cake. Spread the whipped cream mixture over the top, leaving 1/4-inch on each side. Using the edge of the parchment paper, carefully roll the cake creating a jellyroll effect, tuck and roll as you go, peeling back the paper along the way. Put the rolled cake seam-side down and dust the whole cake with the remaining 1/2 cup cocoa powder. Chill 2 hours before serving. You might even put the cake in the freezer for an hour before serving so that it is easy to slice.
To serve, slice cake with a serrated knife and place on chilled plates. Garnish with a light dusting of cocoa powder and fresh berries.
This recipe was created by a contestant during a cooking competition. The Food Network Kitchens have not tested it for home use, therefore, we cannot make any representation as to the results.