How much cake mixture would I need for a 11″x15″ square tin.?
The easiest way to measure the amount of mix needed for an odd shaped tin is by volume. Take a cake tin for which you know how much cake mix to use – ie a 6″ tin takes a 3 egg mix. Fill this tin with water and make a note of how much it holds. Now fill your odd shaped tin with water and work out the ratio of one tin to the other. Multiply the mix for your first tin by this ratio and you should get roughly the right amount of mix. If you have a bit left over use it for cupcakes! That sounds more complicated than it is so here’s an example: Tin A holds 1 litre of water and you know it takes a 3 egg mix to fill it. Tin B (your odd shaped tin) holds 2 litres water Therefore Tin B is 2x the volume of Tin A and will therefore hold a 6 egg mix. This is a very handy method for weird shapes like numbers or teddy bears but will work with any shape.
