Mary Berry and Paul Hollywood make a delicious 3 tier frosted walnut layered cake with buttercream that is perfect for special occasions on the Great British Bake Off Masterclass 2015.

The ingredients for the sponges: 225g self-raising flour, sifted, 1 tsp baking powder, 100g walnuts, finely chopped, 225g butter, softened, plus extra for greasing, 225g caster sugar and 4 large free-range eggs, beaten.

For the caramelised walnuts: 100g caster sugar and 10 walnut halves.

For the buttercream: 125g/4½oz butter, softened, ½ tsp vanilla extract, 2 tbsp milk, 250g icing sugar, For the boiled icing, 2 large egg whites, 350g caster sugar and ¼ tsp cream of tartar.