150g plain flour, plus 1 tbsp
8 eggs, separated
200g caster sugar
5 eggs, separated (keep the yolks for the custard)
200g caster sugar
250g walnuts, a couple of handfuls saved for decoration and the rest chopped
1 tbsp plain flour
1 tbsp potato starch
100g double cream
100g chocolate, chopped
Before making the cake, take the eggs and butter out of the fridge to let them warm to room temperature.
Heat the oven to 170C/fan 150C/gas 3½. Sift the flour and mix it with cocoa. Beat the egg whites until stiff, then add the sugar to them in small batches. Then add the egg yolks one by one, whisking constantly. Sift the flour mixed with cocoa on the egg mixture and gently fold everything together with a spatula. Pour the prepared batter into a 30cm x 22cm shallow baking tin lined with baking parchment and bake it for 35 mins. Cool for 5 mins, remove from the tin and re-line the tin.
To make the meringue, whisk the whites until stiff, gradually adding the sugar, one tablespoon at a time. When you have a stiff and shiny meringue, fold in the finely chopped walnuts, flour and potato flour. Spread the mixture into the tin and cook for 40 mins. Carefully remove from the oven and leave to cool.
For the chocolate glaze, heat the cream over low heat, then remove from the heat, pour the chopped chocolate into it and mix it until it dissolves and the glaze becomes shiny and uniform.
Cut the cooled chocolate sponge cake into two layers. Put the nut meringue on top of the bottom layer of sponge and sprinkle on some of the reserved walnuts. Add another layer of meringue and then the upper layer of chocolate sponge cake and cover the top with chocolate glaze. Decorate with walnuts. Put the finished cake in the fridge for 1-2 hours before serving.