I bought some hardboard at the hardware store and cut it to my size I need. I don't know if I have treat it with somekind of food safe sealant? Or do I use foil?(not a big fan). I will be covering the base with MMF.
You can seal it with Mod Podge, which is a non-toxic decopauge paste. Then cover it with the MMF and have the bottom layer on it's own cake board.
I would cover it with something like press n' seal...
White Contact paper.