Beat the egg yolks and sugar in a mixing bowl with an electric whisk until thick and mousse like. Add the 2 whole eggs and mix well. Fold in the walnuts and bread crumbs, and stirr well to combine.

Whisk the egg whites to soft peaks. Fold a third of the egg white mixture to loosen. Then fold in all the remaining egg whites.

Pour into the prepared cake tin and bake for 30 minutes, until done. Remove from the oven and leave to cool. Remove the cake from the tin and cut into 2 layers horizontally.

To make the cream for topping, mix together the whipping cream and icing sugar. Use half of the cream to spread into first layer, putting more cream at the center. Stack the layers together and spread the remaining icing over the top and sides of the cake.

Decorate with walnuts and serve.