Polish Chocolate and Walnut Layer Cake

Preheat your oven to 170°C (150°C fan/gas 3½). Line a 30 x 22cm shallow baking tin with baking parchment. Sift the 150g of plain flour and cocoa powder together in a bowl and set aside.

Prepare the chocolate sponge: Beat the 8 egg whites until stiff peaks form. Gradually add the caster sugar in small batches, whisking constantly until the mixture is glossy. Add the 8 egg yolks one by one, continuing to whisk. Gently fold in the flour and cocoa mixture using a spatula, being careful not to deflate the eggs. Pour the batter into the prepared tin and bake for 35 minutes. Once baked, cool for 5 minutes, remove from the tin, and re-line the tin with fresh parchment.

Prepare the walnut meringue: Whisk the 5 egg whites until stiff. If you have extra sugar, gradually whisk it in (one tablespoon at a time) until the meringue is stiff and shiny. Carefully fold in the 250g of finely chopped walnuts, 1 tbsp of plain flour, and 1 tbsp of potato starch. Spread this mixture into the re-lined tin and bake for 40 minutes at the same temperature. Remove from the oven and allow to cool completely.

Make the chocolate glaze: In a small saucepan, heat the double cream over low heat until it just begins to simmer. Remove from the heat immediately and stir in the chopped chocolate. Continue mixing until the chocolate has melted and the glaze is smooth and shiny.