Preheat the oven to 425 F. Put one rack fairly close to the top of the oven (not at broil level, but just below).
Mix all the ingredients together until it forms into a dough.
Separate into 6 balls. Roll out each ball between two pieces of parchment paper, and roll it as THIN AS POSSIBLE. Seriously like paper thin.
If you're making a full batch (six dough balls), you won't be able to bake them all at once, so keep the top parchment on until you put them in the oven, so the dough doesn't dry out. Once ready to bake, remove the top layer of parchment and transfer the parchment + dough to a sheet pan. Use a fork to lightly poke holes all over to stop it from puffing up too much.
Sprinkle flaky sea salt over it and bake for 9 to 13 minutes, until crispy and slightly brown on the edges. Keep an eye on it, it burns quickly, so pay attention! But you do want it really golden and crisp and *thisclose* to overbaked, not doughy at all. I've found that it bakes better when it's higher in the oven vs. on the bottom.
Let it cool completely and then break apart into cracker-size pieces. Store at room temperature (I put it in a tupperware container with the lid loosely resting on it...if you seal it, they'll go stale). Use within a week.