I have a Tupperware tub that we use to put fairy cakes in.

It is deep enough to hold 2 layers of cake but the top layer always sticks to the cakes on the base, messing up the icing.

Basically designed a stand so the base layer has 50mm of clearance and about the same for the top.

In my 24cm diameter tub you can squeeze in 7 cakes around the edge and one in the middle. However with the stand and leg placement it is better to have 6 around the edge and the one in the middle. This does mean you go from a max of 8 cakes in the tub without messing them up, to 14.