-Preheat oven to 450 degrees, with a heavy baking sheet on a rack in the middle of the oven.
-Stir together the following:
1¾ cup unbleached white flour
3 TBS chopped rosemary
2 cloves finely chopped garlic
1 tsp baking powder
¾ tsp sea salt
-Make a well in the center and add ½ cup water and 1/3 cup olive oil and gradually stir into the flour with a wooden spoon until a dough forms.
-Knead the dough gently on a work surface 4 or 5 times.
-Divide dough into 3 pieces, keeping remaining pieces covered with plastic wrap.
-Roll out dough 1 piece at a time on a sheet of parchment paper, into a 10-inch circle; dough should be thin, but a rustic shape is okay.
-Lightly brush top with additional olive oil and then press a few rosemary leaves on top.
-Sprinkle with sea salt.
-Slide rounds, still on parchment paper onto preheated baking sheet.
-Bake until golden brown in spots, 8-10 minutes. Transfer to rack to cool.
-Repeat with remaining rounds and fresh parchment paper.
-Break the flatbread into pieces before serving.