Planning to make [[http://www.theguardian.com/childrens-books-site/gallery/2011/mar/18/gruffalo-cake-red-nose-day this cake]] for DS birthday this week. It doesn't state what size tin to use (or it does and the text is over written on my screen) would a 20cm square cake pan do, considering the mix of 6 eggs/300g flour etc? thank you!