Hello! I'm not very familiar with square cakes as mostly do rounds and sheets, so I'm hoping that y'all will be able to help me figure out what sizes these tiers are. The bride also wants a 4th larger tier added to the bottom of this style of cake and I'm not sure what to mark that as either. TIA!!
It looks like a 10-8-7 but that might be just the perspective. Could be a 10-8-6. Since the sides are not straight but cut narrower towards the bottom they fit nicely. I'd cut them upside down by the way and then flip them over as you can mark a 8" or 9"square on the 10" cake top as a guideline. Then just cut down from that line to hit the bottom edge which remains the original size. It's a lot of cake though...if you go with a 12-10-8-6" you'll have close to 172 servings (okay you loose some because of the sides not being straight), 150 maybe.
Oh hang on....looks like they are about 6" high. If you put a cake board at 3" you have even way way more than 150 servings! More like around 220 if you cut 2x2 with 3" height. ..minus the sides about 200. Would need to calculate. But that wasn't your question anyway