Welcome to the Cake Decorators Q&A
That’s big! Have you considered making four 8″ squares and sticking them together? The amount of mixture for a 16″ square is massive if you want a reasonable depth and in my experience very large sponge cakes get overcooked on the edges while still raw in the middle. Another option could be to cook in separate shallower layers and sandwich them together. Just a thought. X
Hi rostas
You won’t go far wrong if you use Mrs Jones vanilla sponge cake recipe here http://www.cakeflix.com/online-cake-decorating-courses/mrs-joness-recipe-for-10-round-deep-sponge-cake. The recipe can be scaled up here http://www.cakeflix.com/blog/how-to-work-out-what-size-cake-tin-to-use. You can either use the ready reckoner or the cakeometer. As an alternative this http://www.bbcgoodfood.com/recipes/10860/ is also a very good recipe. When baking large cakes it is better to bake on a lower temperature for longer. You can also use metal royal icing flower nails inverted in the baking tin before pouring in the batter. The flower nails act as heating cores and help to distribute the heat more evenly through the batter. Have a look here http://www.cakeflix.com/questions/baking-a-16-cake for lots more information on how to bake a large cake more successfully.
Hi rostas, Personally I would do 4 8″ square cakes and join with buttercream or ganache – I would be a bit worried about a 16″ cake being cooked in the middle. Paul goes though joining cakes together in the Loch Ness Cake, and also I don’t know if I would get a 16″ cake tin into my oven at home and have enough air circulation around it for an even bake.
My (standard size) oven is 16″ wide but only 14″ deep!
