Multi-Layered Scallion Pancakes (Thousand-Layer Taiwanese Pancakes)

Directions

1. TO MAKE THE DOUGH: Mix all-purpose flour, bread flour, sugar, and salt together in the bowl of a stand mixer. Bring a small pot of water to 150º F (it should be almost too hot to touch but NOT close to a simmer), then with the machine running on low, add 1/2 cup of the hot water into the flour mixture. Mix for 1 minute or so. The mixture will still look like loose flours with large lumps. Then add 1/4 cup of cold water and mix for 1 minute, and then add 1/4 cup of vegetable oil. Turn the machine to medium-high speed and knead the dough for 5 minutes until shiny and elastic. The dough will be very wet and sticking to the side of the bowl in the beginning (if it seems tacky already, add 1 teaspoon of water), but it should slowly pull away cleanly at the end of kneading. When you lift the dough hook, the wet dough should droop down from the hook slowly.
2. If you must knead with your hands, you can. But keep in mind that this is quite a wet dough and it will stick to your hands while kneading. Cover the bowl with plastic wrap and let the dough rest for at least 1 hour.
3. TO MAKE THE SCALLION OIL AND FILLING: Add 1 cup of diced scallions, vegetable oil, salt, 1/2 teaspoon of ground white pepper and 1/4 teaspoon ground black pepper in a blender and blend until smooth. Transfer into a bowl. Take 3 tablespoons of the mixture out into another bowl and add 1/8 teaspoon of baking soda, mix until combined and keep both in the fridge. Mix the rest of the 1 cup of diced scallion with 1/2 tsp of ground white pepper, set aside.
4. TO MAKE THE FLATBREADS: Divide the dough into 4 portions and set on a well-floured surface. Take 1 portion, dust with more flour, and roll it into about a 1/8-inch sheet. Apply a generous layer of scallion oil (mixed with baking soda) and sprinkle 2 tablespoons of diced scallions over the sheet, then fold it in the same direction 3 times (like folding a letter) into a log, then fold the log lengthwise 2 times into a round shape (try to eliminate as much air as possible while you fold). Set aside (to let it rest) and repeat the same process with the other 3 portions.
5. Now go back to the first dough you worked on (which has had a few minutes to rest) and press it down gently into a thick, flat disk. There will be air pockets in between the layers which will make it hard to roll out, so pierce the dough a few times with a fork and dust with only enough flour to prevent sticking, then roll into a large circle slightly thicker than 1/16 inch. (Be careful not to over-roll it because you’ll risk flattening all the layers.) If the dough springs back stubbornly, rest it for another 2 min. If you want to keep the flatbreads in the freezer, laminate the rolled-out doughs in between two sheets of parchment paper and tuck inside a zip-lock bag. Keep frozen until needed.
6. Heat 2 tablespoons of oil in a large, nonstick skillet over medium heat. Carefully lift the dough up and transfer to the skillet. Cook over medium-low heat, add more oil if needed, and cook until golden brown on both sides (it’s important to add enough oil). The baking soda will create bubbles in between layers during cookings. Right off the skillet while it’s still hot, brush the top with more scallion oil (without baking soda). Serve immediately.