Need a recipe for a birthday cake

[leakyR]

DS1 first birthday on Saturday.

I have a 13"x9" oblong tin and plan to decorate it with a rolled icing and a picture of a giraffe. i'm fine with decorating but need a good foolproof recipe for a nice moist vanilla/yellow cake to go underneath the icing.

Mostly adults and babies coming to party so the target audience is fairly grown up.

I'd make a 6 or 8-egg victoria sponge but am aware this is not 'foolproof', it's just easiest for me because I do it so often.