How to make Mary Berry’s frosted walnut layer cake

By Elena Silcock

The Great British Bake Off is back on Wednesday and I, and everyone else at delicious. HQ, can’t wait.

The team here (not the food team though, that would be cheating) have taken on a mission – to make the technical bake, set by judges Paul Hollywood and Mary Berry, from every show. The first week is all about cake and the gauntlet has been thrown down by the doyenne of baking herself, Mary Berry, in the form of her frosted walnut layer cake.

I was unlucky enough to be first to take on the technical challenge…

The bake
At first glance this Mary Berry classic may seem like a rather simple walnut cake but the addition of American frosting makes it a worthy choice for the first technical challenge. Three delicate layers of walnut sponge, filled and covered with a rapidly setting meringue frosting, could provide some stumbling blocks even for experienced bakers.

How to make the cake
To start off  you have to make a walnut sponge using self-raising flour, butter, sugar, eggs, baking soda and chopped walnuts. The batter is spread evenly between three 20cm lined baking tins and popped into the oven. So far, so good.

Reaching the peak of the bake
Once the layers are baked and out of the oven, it’s time to make the frosting by whisking together the egg whites, caster sugar, cream of tartar and a few tablespoons of water in a bowl set over a pan of near boiling water. It sounds easy enough, but the meringue needs to be whisked for 9-12 minutes until the frosting is stiff, glossy and exactly the right consistency.

What are the tricky bits?
The batter is made using the all-in-one method – all the ingredients are beaten together in one bowl so, as long as the measurements are correct and the batter is cooked at the right temperature for the right length of time, it’s pretty straightforward.

The frosting is the trickiest bit to master, not to mention a demanding whisking time that could easily qualify as a gym session. Timing is key, so setting a timer for 9-12 minutes whilst whisking will help the contestants to avoid taking the mixture off the heat too early (or when their arm begins to feel like its going to fall off).

There is also a need for speed as the icing will cool and set quickly. The contestants will need to fill and coat the delicate walnut sponges while the frosting is still soft. If this isn’t enough of a challenge, the contestants also need to complete all of this while leaving enough time for the icing to set before the cake is placed before the critical eyes, and tastebuds, of Mary and Paul.

How did it turn out?
My attempt at the bake went surprisingly well. The sponge was a little crumbly, but the frosting went smoothly. I followed Mary’s recipe to a T and had a bit of an advantage in that I’d been given all the timings and measurements, as well as explicit instructions regarding the tricky method of making the frosting. The contestants will not be so lucky – I can’t wait to see how they fare.