Rosemary Crackers

These delicate, gluten-free crackers taste like a rustic flatbread, with a crisp crunch and a little give. They’re best when eaten within a day of baking.
INGREDIENTS
1 packet active dry yeast (about 2½ tsp)
2 tsp sugar
1 cup warm water
1 cup sweet rice flour
1 cup potato starch
1 cup tapioca flour
¾ cup ground flaxseed
2 tsp kosher salt
1 tsp baking soda
1 tsp xanthan gum
1 large egg
¼ to 1/3 cup olive oil or grape-seed oil, plus more for brushing
Cornmeal, for dusting baking sheet
Fresh rosemary, chopped
Sea salt
DIRECTIONS
1 Stir yeast, sugar, and water together in a small bowl. Set aside.
2 Combine dry ingredients in a bowl. Sift them into a larger bowl, adding any flaxseed remnants back in at the end.
3 Stir yeast-water mixture and egg into dry ingredients. Add oil—up to 1/3 cup—stopping when no dry spots remain and mixture begins to resemble cookie dough.
4 Set dough aside and cover with a clean dish towel; let rise for 1 hour.
5 Preheat oven to 450 degrees. Sprinkle a baking sheet with cornmeal.
6 Between 2 pieces of parchment paper roll a third of the dough as thin as you can make it, as big as the baking sheet.
7 Transfer dough to the prepared sheet. Brush the top with olive oil and press fresh rosemary and sea salt lightly into the top. Bake for 8 to 10 minutes, or until the dough has hardened. Repeat with remaining dough. Allow dough to cool for at least an hour. Break into shards with your hands, and enjoy.