Sponge Roll with Bittersweet Chocolate Filling and Icing

Sponge Roll with Bittersweet Chocolate Filling and Icing
Source: Maida Heatter's Book of Great Chocolate Desserts (Andrews & McMeel Publishing, 2006 ed.), pg. 47.

This is a soft, delicate sponge cake filled with chocolate icing that isn't too sweet. I had a few problems with the recipe and it was partly due to not following the rules. Do use butter for the pan as instructed as the cake doesn't come off the foil easily with cooking spray. This wasn't a complete disaster but I had to be very careful when removing the foil. Butter would have probably made this easier.

I also had problems with the filling getting to the right consistency but I just returned it to the heat and started over again and it turned out fine. 

I didn't use the chocolate shavings as I didn't have enough chocolate so I just used chocolate chips. 

Sponge Layer

1/4 cup sugar
4 large eggs, separated
3 TBS. sifted all-purpose flour
Pinch of salt
3 TBS. confectioners sugar  

Preheat the oven to 350 and line a 15x10x1 jelly-roll pan with foil. Butter the foil.

Add 3 TBS. of the sugar to the egg yolks. Beat on high speed for about 5 minutes until the yolks are cream-colored.

Add the flour and beat on low speed.

In a separate mixing bowl (with clean bowl and beaters), beat the egg whites, adding the reserved 1 TSB. of sugar, until they hold a shape.

Transfer 1/3 of the egg whites to the egg yolks and gently fold in. Add the remaining egg whites, 1/3 at a time, and fold in.

Turn the batter into the prepared pan, making sure that you spread it to all four corners of the pan. Bake for about 15-18 minutes until the top springs back when lightly touched.

After removing from the oven, sprinkle the cake with confectioners sugar. Cover the pan with a cookie sheet covered with wax paper and invert the cake onto it.

Now carefully peel away the foil. 

Roll the cake and the wax paper together. Allow the roll to sit until it has cooled.
Prepare the glaze. 

Bittersweet Chocolate Glaze

6 oz. semisweet chocolate
1 oz. unsweetened chocolate
3 TBS. prepared coffee
2 TBS. light rum or cognac
1/2 to 1 cup of chocolate shavings
Confectioners sugar

Melt both chocolates with the coffee in a heavy saucepan or double boiler over low heat. Remove from the heat and stir in the rum (or cognac). Sit aside and allow it to come to room temperature.

 

After the glaze has cooled, sit it over a bowl of ice water until it has thickened. It will thicken quickly - if it becomes too thick, return it to the oven eye and reheat. When it has reached the desired consistency, unroll the cake and spread about 1/3 of the glaze over it. Roll the cake again (this time without the wax paper!).

 
 

Use the remaining glaze to cover the outside of the cake.

Transfer the cake to the refrigerator for about 30 minutes so that the glaze can set. Then dust with confectioners sugar. Let the cake stand at room temperature before serving.