I have been asked to make a 12x18 birthday cake for someone. I am planning on using 3 duncan hines box mixes. I normally add a box of pudding when I make a 9x13 and was wondering if I should follow the same procedure and add 1 box of instant pudding per cake mix? I know this is a dumb question but this is the first time I have made a cake this large and don't want to mess it up. I also would like to know if you would recommend using a metal rose nail as a heating coil on this size cake. I have heard that people have done this but not sure if I need to do it on this size cake? Thanks so much!

I would use a box of pudding mix per box of cake mix. Thats what I havae always done. Also it never hurts to use the flower nail as a heating core!

thank you so much!