I am making a 16" high mountain cake with an oval base that is 18" at it's widest point. I have never used a masonite board before and have a few questions.
Should I get 1/4" thick or 1/2" thick?
20" round or 22" round?
Is it easy to cover in fondant?
Does it change how I use an SPS system?
SPS doesn't care what it's sitting on, but masonite is the best bottom cake board material, hands down. I would recommend 1/2 inch for sure, and make it 23 or 24 inches. Definitely easy to cover in fondant.