standing roll cake

Continuing in the "try something new" theme of GBBO (Great British Bake Off), I made a standing roll cake. It's not dissimilar from a Swiss roll, but you make a bigger roll by cutting the sponge into strips and making the roll shorter and stouter... then you stand it up! Once you roll it, chill it, and stand it on end, you frost the outside and decorate.

So you can see here I baked a sponge in a standard half-sheet pan, then cut it vertically in thirds. I spread the coffee mascarpone cream on it, then started rolling it tightly. When I finished rolling the first third, I spread cream on the second third, then placed the roll on top of that, covering the seam, and continued rolling tightly. I then repeated with the final strip of cake, then chilled it briefly before standing it up. 

I decorated the outside with the remaining coffee mascarpone cream, then did a chocolate ganache drip on top, and I fancied it up with some tempered chocolate shards. I like when the drip doesn't run all the way down the side. The way I combat this is twofold: 1) a thicker ganache, which I let set until it's still runny but fairly cool, and 2) pouring it over a chilled cake, so it chills on contact and doesn't run too freely. I tempered the chocolate for the shards so it wouldn't "bloom" (get those white speckles on it that means the cocoa butter has separated from the chocolate solids). Once it was set, I cut it into triangles and stuck them in the cake.

I brought the cake to a GBBO finale viewing party, and one of the other guests (who was only 14 at the time!) baked the traditional GBBO cake with the missing raspberry. Here's a pic of the two dessert offerings for the night (no one suffered with that much chocolate deliciousness!).

And although it's not a great pic, you can see here that the cool thing is that the roll, when turned on it's side, makes vertical layers! The idea was to have an even thickness to the layers and to the filling. It is so neat-looking!

I can't locate the exact recipe I used for this cake, but this is the most similar one I've found. Obviously, I emulated the look of her cake, although I didn't bake the cookie base, I used just one 13x18" cake layer, and I don't recall using apricot jam. (Though I love apricot jam and it would have been delicious with those flavors!) Her cake was beautiful and I hope I did it justice!