Lavash (Armenian Flatbread)

Place flours, cornstarch, and yeast in a medium bowl and whisk to combine. Add milk, oil, and honey and stir with a wooden spoon or dough whisk until combined and no dry flour remains, 15 to 30 seconds. Cover and let sit at room temperature for 20 minutes. Andrew Janjigian Add salt to top of dough and, using lightly-moistened hands (or a dough whisk), knead in bowl until salt is fully incorporated and dough is even in texture, about 30 seconds. Cover and let sit at room temperature for 45 minutes. Andrew Janjigian Using lightly-moistened hands, knead dough in bowl until uniform in texture, 5 to 10 seconds. Cover and let sit at room temperature until puffy and not quite doubled in volume, 30 to 60 minutes. Andrew Janjigian Transfer dough to lightly-floured counter, flour top of dough lightly, and divide into 4 equally-sized pieces (about 100g each). Form each piece into a smooth, taut round. Coat each dough ball lightly with oil, then transfer to lightly-oiled containers or a lightly-oiled tray, spaced at least 2 inches apart. Cover and refrigerate for 12 to 24 hours. Andrew Janjigian Adjust oven rack to lower-middle position. Place baking steel or stone on rack, and preheat oven to maximum temperature, 500 or 550°F (260 or 290°C), for at least 30 minutes if using baking steel, or 1 hour if using a stone. Andrew Janjigian Once oven and baking steel/stone are preheated, set broiler to high and remove dough balls from refrigerator. Set a wire rack inside a rimmed baking sheet, cover with a clean dish towel, and set aside. Place 1/3 cup (45g) flour in a mound on center of countertop and transfer one ball of dough to flour. Flip dough ball over once or twice to coat thoroughly with flour. Using a rolling pin, roll gently into a roughly 14- by 11-inch rounded rectangle, flipping dough as needed to coat with flour and prevent sticking or tearing. Andrew Janjigian Using a fine pastry brush, brush excess flour from top surface of dough. Transfer lavash to an 18- by 13-inch sheet of parchment, and then to a lightly-floured wide peel, rimless cookie sheet, or inverted rimmed baking sheet. Using misting bottle, mist top of dough lightly with water. Transfer to baking surface. Andrew Janjigian Bake until dough puffs up into a single balloon, about 30 seconds; the color change will not be substantial. Flip dough, remove the parchment sheet, and bake for an additional 10 seconds. (If dough does not puff completely after 30 seconds, flip anyway.) Transfer to prepared cooling rack and cover loosely with towel. Using bench scraper, gather flour into mound on countertop again. Repeat rolling and baking with remaining dough balls, one at a time, reusing the same parchment and stacking finished lavash on top of previous ones. Allow the stack of lavash to steam for at least 15 minutes. Brush off excess flour from each lavash, and serve. Andrew Janjigian