Use up any ripe bananas in this chocolate and nut-topped cake. This sponge tastes best after being left in a cool place overnight.
If you do not have a ring tin, you can bake the cake in a 20cm (8in) round cake tin. Grease and line the tin and bake for 40-45 minutes.
To make a cake everyone loves, remove the banana and walnuts and top entirely with melted milk chocolate.