[Acrylic-bob]

Ok, I can see I'm not going to get away with this so I will have to risk the wrath of the Guild of Master Bakers and give away a trade secret. The stuff is called crossing paste and it is made from a loose mixture of flour, oil and water and is piped onto the bun before it is proved. As the dough beneath it rises, it appears to sink into the bun. It does not go as brown during baking as the rest of the bun because of the higher percentage of water and oil.

I hope you realise that I will probably be struck off for this.