However... I must have not split the sponge mix into thirds correctly, as there's way more plain than blue and red, so the effect is lost. And the colour faded loads on baking, adding to the poor effect from outside. Then I tried to hide the cake by icing it in white and drizzling red and blue icing in stripes all around. It seemed ok to me, but Mr Becca's face was a picture when he walked into the kitchen. I still can't decide if he was being honest or a tad cruel in his assesment - so I added the red, white and blue stars. It looks like fireworks, right?