Cake for Quintana: Mary Berry’s Frosted Walnut Layer Cake
This week I made a cake for the white jersey. It’s worn by the highest placed young rider (25 and under) in the Tour. At the moment, it’s being worn by Nairo Quintana. Quintana is a great climber, so I decided to make a cake that, in the picture in Mary Berry’s Baking Bible at least, is covered in glossy white peaks of American frosting. For the romantics, these could be the peaks of the Pyrenees.
The recipe for the cake itself was simple. One of Mary’s all-in-one sponges where you simply put all of the ingredients into a bowl together and beat the mixture until it’s smooth. Usually, for a sponge, I’d cream butter and sugar together first, then add eggs and, finally, fold in flour. The all-in-one method works because you use self-raising flour and baking powder to get the cake to rise. Mary does warn you though, that you have to be careful not to overdo the baking power, because this will cause the cake to sink.
I mixed my ingredients (softened butter, caster sugar, eggs, self-raising flour, two very carefully measured level teaspoons of baking powder and finely chopped walnuts) together until the mixture was smooth. Mrs Patmore’s arms would, once again, have come in handy for this one. I could only manage to stir the mixture about ten times round before having to have a break.
I divided the mixture between three 20cm tins and put them in the oven at 140° fan. The recipe says that the cakes should need between 25 and 30 minutes and should be golden and springy. My cakes took 40 minutes and, although they were springy when I took them out, they were pale and pock-marked with air bubbles. They also sank a bit in the middle, despite my meticulous measuring of the baking powder.
I suppose, since it was going to be covered in frosting, the look of the cake wouldn’t matter too much, but the frosting was the difficult bit. The cake should have been easy.
Mary Berry uses a simple American frosting in her recipe. She makes this by whisking egg whites, caster sugar, water and cream of tartar over a pan of hot water for 10-12 minutes. She calls this the “instant” version (although 12 minutes of whisking doesn’t sound very instant to me).
“Proper” American frosting, she says, is made by boiling sugar and water and adding it to whisked egg whites. I decided to go for the “proper” version as a challenge. A sugar thermometer was required, which I’ve always found difficult to use (my previous attempts have usually ended up in disaster).
I put caster sugar and water into a pan to dissolve. While this was going on, I put 2 egg whites into the bowl of the KitchenAid and whisked until they were stiff. I then stood over the sugar/water mixture and watched the sugar thermometer very closely. It had to reach 115°C (which is marked on my thermometer as “soft ball” stage).
It got there eventually. I took the pan off the heat, waited for the bubbles to subside (as per the recipe) and poured the syrup slowly onto the egg whites with the KitchenAid whisking away. According to the recipe, the frosting would be ready when the mixture stood in peaks and started to become matt around the edges. I whisked until the mixture peaked. I wasn’t sure what “matt around the edges” meant. It’s possible that I may have over or underdone it, because when I stopped I didn’t have the glossy mixture that covered Mary Berry’s cake.
The recipe warns that you need to work fast with the frosting because it sets quickly. It sure does. I did manage to sandwich the layers of my cake together and I just about got it covered before it started to set. This is my end version.
Was it worth it?
It’s a bit more Côte de Buttertubs (Yorkshire Dales) than Col du Tourmalet (Pyrenees), but it looked OK. The question was, given the qualms I had about the cake, how did it taste?
Well, it was really very good. A very decent walnutty sponge. I’m not sure I’d use the all-in-one method for a cake that wasn’t going to be covered though. The whole too-much-too-little baking powder question seems a bit too hit-and-miss. The icing, despite being a bit on the bumpy side, was good too. Very sweet, crisp on the outside with a slight chewiness underneath. Any tips on how to make glossy Col du Tourmalet peaks with it would be very gratefully received.