Replicating commercial gluten-free/non-gebrokts matzo -- where to start? I'm on a somewhat restricted diet right now in which I'm not allowed to eat any grains of any kind. It turns out that the Yehuda gluten-free matzo and Manischewitz gluten-free matzo-style crackers are entirely grain-free, being made of tapioca and potato and eggs.

Unfortunately, they're only available during Passover, and even then they're somewhat hard to find and somewhat expensive. Therefore I'd like to make my own. I'm not expecting a perfect clone, but any kind of approximation would be fine as long as it tastes good.

All of the gluten-free/grain-free matzo recipes I found online are made of nut flour, which I don't like much and I'd rather not use.

Obviously it's good to "just experiment," but in this case I have no clue where to start. What should I try first? How would one go about trying to "clone" a product like this?
Here's a recipe from Joy of Kosher. The flours and starches may be a bit hard to find in stores, but they'll be on Amazon. As a matter of fact, the matzo is on Amazon too, but you're right, it's pretty spendy.