Preheat the oven to 450°F and place a flat baking sheet on the middle rack.

Mix the dry ingredients and the rosemary in a medium bowl. Add the oil, and gradually, the water, until you have dough that pulls away from the sides of the bowl. Turn out onto a lightly floured surface and knead for several minutes.

Divide the dough into three parts. Roll one piece of dough out on a sheet of parchment paper to a disc about 10 inches across. Brush the top of the dough with a little olive oil and sprinkle with some sea salt. Slide the dough, parchment and all, onto the hot baking sheet in the oven. Bake for 8 to 10 minutes, until it is starting to turn golden on top. Allow to cool. Repeat this process with the other two pieces of dough. When the three flatbreads are cool, break into pieces to serve.