Fillables 29cm Square Cake Tin 4 "Mixture in recipes not enough" Jane 06 February 2017 After reading the reviews I decided to use my own sponge recipe and calculated the dose of a total of 6 eggs (3 eggs per tin). It still wasn't enough to cover the holes, but next time I'll up it to 8 eggs! I also worried about it getting the cake out of the tin, so I cut out a piece of baking parchment - yes it took ages! - but the cake came out easily. It looks really good and the possibilities for fillings are endless!! I think I'll be using this tin a lot!