The tiers are 8", 10", 12", & 14" squares, with air (flowers) between them. I will be using the 5" Grecian Pillars between each tier. My question is what size separator plate would be best to use under the 8"-10"-12" tiers? The bottom border for each tier is not a big border. I was thinking this: For example, with my top 8" tier: Use a 9"in. square cake board underneath the cake, place that on an 8" square plate? Same size plate for the cake, but the cake board (under the cake/above the plate) being 1 inch bigger.
Will this work?
P.S. Are there any helpful threads/links on cutting & serving these pillar cakes?
You'll have to take the cake apart to cut it. As For the plates, I'm not understanding why you want you cardboard to be an inch larger than the cake. Do you need the extra ledge for the design? If not what are you going to do to fill the extra space?
On a general note, there is no problem using a plate a size down from the cake and board.