Make a 12 oz flour/sugar/butter quantity of Victoria Sponge Cake and distribute it among three 6 inch round tins and one 6 inch square tin. Bake and allow to cool.
Follow the diagram below to cut the cakes. The stripey bits are those you may eat while you ice the cake.
[redrawn from a thirty year old magazine cutting]
Then assemble the pieces thus
and ice and decorate the cake as suits yourself. Dolly mix, mini smarties, and pretty sugar flowers are useful embellishments. Chocolate icing makes good hair.
I hope that my response isn't too late for any birthdays and that seven beautiful doll cakes will be created in a flurry of hope and toil and iced redemption.