A jelly roll is simply a thin sponge cake baked in a broad flat 15 x 10 x 1-inch rectangular baking pan and then rolled up around a filling. Typical fillings include jelly or preserves, custard, cream, buttercream icing or mousse. The ever-popular Christmastime treat is the Buche de Noel, a jelly roll filled with buttercream and coated in chocolate.
You want a jelly roll cake to be light and fine-grained, but it should also be a bit elastic and flexible so that it can roll without cracking. The texture of the cake is light and flexible enough to make a delicious roll. To ensure that the jelly roll will come neatly out of the pan, spread Pan Release, butter, or margarine on the bottom and sides of a pan. Line the bottom of the pan with greased wax paper or baking parchment.
While the cake is cooking, place a clean cotton kitchen towel that is larger than the size of the pan on a hard surface, such as a cutting board or countertop. Sprinkle the towel with confectioners (powdered) sugar or granulated (white) sugar. This sugar will prevent the cake from sticking to the towel.
As soon as the cake comes out of the oven to cool, invert the pan over the towel sprinkled with sugar. Lift off the pan and carefully peel off the paper. Don't worry if thin layer of cake remains on the paper. With a serrated knife, carefully slice a l/8-inch strip off of crisp ends of the cake -- this will make rolling the cake easier and prevent cracking. You can use a long piece of dental floss, held tightly, to cut the edges in a sawing motion, which will make a nice even edge. Fold one short end of the towel over the end of the cake, then roll the towel and the cake together, pressing gently. Be sure to move slowly and carefully throughout the entire rolling process. The towel will end up coiled inside the cake.
Place the cake seam side down on a wire cooling rack to cool for at least 1 hour. It can be left out to cool for several hours or even overnight before unrolling and filling it. Once filled, cut the jell roll with a serrated knife, using a sawing motion. Otherwise, you may press down too hard on the roll and squeeze out the filling and distort the appearance of the cake.
How to assemble the jelly roll:
- Unroll the cooled cake leaving the cake on top of the cotton towel. The cake will be slightly wavy.
- Spread the cake with filling as directed in the recipe. Generally, the filling is spread to within 1/4-inch from the sides of the cake. This will prevent the filling the oozing out when rolled.
- Start at one end and roll the cake towards you. After nearly a complete turn pick up the cloth and use to continue rolling.