Birthday cake guidance needed for novice - DD2 would love a blue one - ?

[franch]

I'm fine at baking the actual cake - have done plenty of those - but have never gone in for fancy decorating - usually just a bit of butter cream or a nice chocolate ganache, topped with some (bought) marzipan animals or sugar flowers.

But a blue cake - ? Would I need to use roll-out icing? If so where do you get it and how do you use it? Does it require skill?

I was thinking about hiring a number 3-shaped tin, but would obviously only do that if the icing isn't going to require any dexterity.

I need ideas that are minimum effort and low stress for a clumsy, uncreative novice, but of course give wonderfully impressive results

use paste colouring to colour buttercream and smear it on a 3-shaped cake - no dexterity required.

That sounds do-able - it would give a sort of 'textured' finish rather than a smooth one, wouldn't it? Which is fine.

Where do you get paste colouring? Normal supermarket shelves?

you migth be lucky in a big supermarket but otherwise you'd need a cake decorating shop - or try online eg here - you often get stung for high postage though so shop around

outlining the edges of the cake in co-ordinating sweets (dolly mixtures are good) can look very smart at v low effort

(NB paste colouring also works well for glacé icing if you'd rather have a smooth glossy finish)

This is all so helpful MrsB, thanks. Will def do the sweets.

Never done glacé icing before (except maybe on biscuits or fairy cakes) - how foolproof is it on a big, odd-shaped cake?

dead easy, v similar to ganache technique

sieve the icing sugar really well
don't make it too runny
(also good idea to make more than you think you need - use any spare up on fairy cakes or plain biscuits eg rich teas)
stand cake on cooling rack over tray or on final presentation board protected with strips of foil / greaseproof
pour icing lavishly over cake making sure enough drips down sides to cover them. Assist with spatula if necc (same as chocolate ganache technique)
leave till set
remove foil/greaseproof or transfer carefully to board

Ooh I've got choices now ... will have a think and maybe a couple of trial runs.

Many thanks MrsB