Preheat oven to 350°F (180°C).
Mix all dry ingredients together well. Stir in the oil and begin stirring in water a little at a time. The dough will need to be formed into a ball, if it is too dry add a little more water, if too wet, more flour.
Divide the dough in half and roll each half into a ball.
Use a Silpat or cut a generous amount of plastic wrap and dust it with a gluten-free flour. Flatten one ball into a rectangle, place it on the Silpat or plastic wrap and sprinkle with some more flour. Place another large piece of plastic wrap on the dough and using a rolling pin, roll the dough out as thinly as possible. It might be necessary to peel off the top layer of plastic and re-dust a few times.
Peel off the top layer of plastic, dust with a little more flour, place a baking sheet over it, slide another baking sheet under the bottom plastic wrap, flip over, remove the other sheet of plastic wrap and bake.
A nice touch, although not necessary, is to glaze the crackers before baking with an egg white or cornstarch glaze.
Mine were a little less than an eighth of an inch, but less is literally more! Crackers, that is.
Bake for approximately 12-15 minutes, until lightly browned and crispy. They will crisp up more after they cool off. After cooled, store in an airtight container.