Aron’s request for a biohazard warning sign seemed like a wonderfully fitting choice for a tenth birthday cake, given kids’ often cavalier attitude to hygiene!

It was simple to make and gave us the chance to discuss how to work out the lengths of the sides of an equilateral triangle if one knew how tall it could be (the width of the cake carrier).

I was able to get a really toxic background colour by mixing in a little green with the yellow.  The symbol itself, I cut out of home-made black fondant using improvised cutters (random kitchen items) of the appropriate diameter, offsetting them to get the narrow/wide shape, then cutting in the gaps once it was in situ.

The irony of the image was probably lost on the children (though not the grown-ups) and it certainly didn’t stop anyone from eating it, as you can see!