1) Preheat oven to 325°F. Line a half sheet pan with parchment paper and spritz with cooking spray. Set pan aside. In a large bowl, whip the egg whites to soft peaks. Add 1/2 cup of sugar gradually, continue beating the whites until stiff peaks form. Set whites aside.
2) In a small bowl whisk together the dry ingredients, including the remaining one cup of sugar. Set aside.
3) In the bowl of a stand mixer, mix the egg yolks, oil, milk, vanilla and hazelnut flavoring until well blended. Mix on medium speed until lightened and pale lemon colored. Add the dry ingredients and continue to mix, about 1 minute until well incorporated.
4) Remove the bowl from the mixer. Using a large spatula, gently fold the egg whites into the batter, 1/3 at a time. Use gentle motions to preserve the air in the whites. Pour the batter into the prepared pan and bake for 15-18 minutes or until golden brown on top and the cake begins to pull away from the sides of the pan slightly.
5) While the cake is baking, prepare the ganache filling: Heat the cream until just simmering. Add the chopped chocolate and remove from the heat. Stir gently until the chocolate melts completely. Remove from the pan and place in a large bowl to cool. You may refrigerate or freeze the ganache to speed the cooling. Once the ganache is cooled to pudding consistency, whip with a whisk or hand mixer until fluffy and frosting like.
6) Remove the cake from the pan by lifting the parchment paper. Place cake side up on the counter and trim off the edges of the cake to make rolling easier. Turn the cake over and peel off the parchment paper.
7) Brush the cake with the simple syrup; let it sit for 5 minutes so the syrup can soak in.
8) Using a large, clean kitchen towel well dusted with confectioners' sugar, roll the cake up as though the towel were the filling. Cool the cake rolled up for 20-30 minutes. Unroll the towel and remove it. Spread with the prepared ganache filling and re-roll. Place in the fridge to chill for 20-30 minutes. The roll can be frozen at this point for up to 3 months.
9) To decorate the cake, melt 8 ounces of white chocolate very slowly over low heat in a double boiler. Remove the cake from the refrigerator and spread a thin layer of chocolate over the entire surface. Return to the fridge to set up, 10-15 minutes. Add a second layer of white chocolate to the cake, spreading the chocolate to resemble tree bark. A fork may be used to add texture by dragging the tines through the cooling chocolate. Once the chocolate has firmed, decorate as desired with a dusting of confectioners' sugar, cocoa or chocolate curls.
Hi Jane- I'm sorry to hear you had so much trouble with this recipe. The recipe is designed for a half sheet as you mentioned which is nearly twice the area of our current jelly roll pan, so we would certainly recommend a reduction if you are not using the pan called for in the recipe. In regards to the cracking, you may have added a bit too much flour if you used a different method of measuring flour than we do here and it also may have resulted from a bit of over-baking. If you would like to give our Baker's Hotline a call a 855-371-2253, we would be happy to further discuss the recipe with you and figure out how to get everything back on track for a beautiful roll on your next attempt. Happy baking! Jocelyn@KAF