Preschool said she is okay with traces, so as long as I do my best and absolutely do not include any egg products in the cake, it should be fine. I will email to confirm what that means before starting to bake, though. They are excellent there and she is now in her second year with them, so I really do trust their advice. I don't want to ask her parents because my brother has SN, and I remember how skin-crawly people's special concern could be. Really creepily self-congratulatory and pitying. I'd hate to be like them, and the parents think I was after weirdy virtue points. I just remember being a greedy little girl who loved cake, and it would have upset me to watch all the other kids eating one when I couldn't, week after week. And I like baking, anyway.
If I were someone who bought my son's cake I couldn't do this, so may as well take advantage of one of my few Proper Mother skills. (I am crap at all crafts without the greed incentive!)
My plan is:
Scrupulously clean the worksurface I will use for her (it's granite so you can really scrub the hell out of it) and keep that as "her" worksurface, opposite side of the kitchen to the main one.
Make her mix in a bowl by hand, with a spoon (as it's a small quantity), on the extreme opposite worksurface. Bake the egg-free cake mix in cupcake cases, on a bun tray that has also gone through an intensive wash (though obviously the paper will act as a barrier). (Will need separate baking as shorter time, so will get out and cool in the tray while putting in the main cake.)
Make the main cake in the stand mixer, using silicone beater attachment. bake.
Wash main bowl by hand, then put through heaviest wash in machine, then again by hand. Can then use that bowl and the metal beater attachment to make the buttercream icing. Do same thing with the saucepan and another bowl for the chocolate ganache.
Ice and decorate baby hedgehog.
Put the baby hedgehog into a sealed cardboard cake box before the other cake gets out of the oven to cool/ice.
Does that sound okay? I want to put a layer of buttercream icing in the middle of both cakes, and then choc ganache on top to stick the Flakes into, but I can always make her buttercream in another fresh bowl if the beater one might be a worry? (It's a steel one, so you really can be sure it is clean, I think.)
Thanks for the advice, I am genuinely appreciative. I want to do something nice for her, not make her ill! So any extra tips will be gratefully received.