Miscellaneous Food: Pierre Herme's Blackforest Gateau
I decided to attempt Pierre Herme's Blackforest Gateau, not once but twice. The first time, I was motivated by having been given a small bottle of Amadei cherries in thickened syrup, which had been sitting in my fridge and which I wanted to finish up. I'm not a fan of Blackforest, nor Kirsch, so it seemed an odd choice, but I remembered that my cousin had made this cake sometime back and it was really light and good.
It was indeed good and I decided to buy a tub of griotte cherries, so that I could try the recipe a second time. These griotte cherries are actually not the same as Amadei cherries, the griottes are smaller and more red, the Amadei cherries, which I think is a specific brand of cherries, are larger, more turgid and a dark blackish colour. However, both work just as well.
The recipe is from his book Chocolate Desserts, with Dorie Greenspan, so I'm not reproducing it here. The first time I made the cake, I used a 9 inch round tin, which wound up being very large (and also high) and so the second time around, I used two 6 inch tins, which worked out much better. Most times, it’s a lovely thing to have two smaller cakes. It is at least a two-day process and it really should be done over two days to save yourself the stress of doing it all on one single day, so on Thursday (I was planning to serve the cake on Saturday) night, I made the chocolate sponge.
This is similar to a Devil's Food cake with about 6 egg yolks going into the recipe. I did 1.5x the recipe because I wasn't sure if there would be enough cake to go around (if you make his macarons, you will know that the proportions for the ganache are usually larger than the shells). However, this was a mistake, please trust the master and don't double either the sponge or the mousse recipes for this cake. This is what led to both the layers and the cake being so high, the first time.
The second time around, I used the chocolate chiffon from Mont Blanc because chiffon is lighter and airier. This produced a slightly different set of problems. Although the chiffon was indeed light, I realized that I personally don’t really like the sponge that light, although other people who sampled the cake did. Also, the chiffon was much softer, so the layers took more time to adhere to each other and the cream, it pulled away from the sides when baking (which you can correct for in the creaming layer) and lastly, the softness made it hard to cut without squeezing down through the cream layers, which then made the layers messy.
I also soaked the cherries and made the chocolate mousse. Soaking the cherries involves removing them from the syrup (the Amadei syrup is lovely) and cooking them slightly in a syrup of port, pepper, lemon peel and cinnamon. They are then left to soak overnight and you have to drain them well before use, so they don't bleed into your cake. I really like that the cake is fairly organic, with the griotte cherries, rather than the traditional, store-bought bright red and somewhat artificial maraschino cherries. I melted whipping cream and chocolate together, then let it cool overnight and whipped it to form the mousse.
The early pictures you see here are the process of assembling and stacking the cake. The first time, I made three layers and the second time, I made four sponge layers. Each pair of sponge layers is then sandwiched with the chocolate mousse, or the whipped cream and cherries.
Just a tip, rather than assembling the cream layer as we were doing, spreading the cream and embedding the cherries in it, it is better to site the cherries first and then pour and smooth the cream over them, so that the cream layer is only as thick as the cherries themselves. In our case, we found the cream layer to be too thick. Remember also to press down on the sponge layers as you are constructing the cake.
As you can tell, for the second cake (above) the levels came out the right height but for the large first cake (below), I should have levelled the layers into 0.5-0.75cm widths, rather than thick layers. These are squeezed into a cake round, or a springform cake pan. You will want to line the sides of the pan with a plastic strip to keep the cake upright and also to help separate it from the springform tin. This was the first time that I've used one of the plastic strips (mine was just home-made) and it was quite a revelation to see how neatly the layers formed and the plastic "skin" that peeled off after the cake was chilled.
The cake is then topped with shaved chocolate and piped swirls of cream. You can then choose (or not) to frost the sides of cake with the remaining whipped cream. The first time I made the cake, I topped it with chocolate mousse and the second time, with the whipped cream, either is fine really, although if you intend to frost the whole cake, then the whipped cream topping is easier. In my first go-around, I had altogether too few cherries within the layers- remember that you are slicing these cakes and for each slice to contain cherries, you need to really fill the breadth of the layer with cherries, as opposed to just having them dotted in the layer. So that too, was corrected the second time around.
The whole cake then needs to sit until it sets and is cold enough for the layers to adhere and be sliced. The texture is really lovely and the cake in general was well-received with the older folk saying that it is not too sweet (if you want to make it less sweet, use half Manjari chocolate for the mousse, as suggested and half Arugani or even a 99% bitter cocao).