In large mixing bowl, combine flour and salt. While mixing with a fork or chopsticks, pour ⅓ cup boiling water into the bowl. Add 3 tablespoons of room-temperature water, 1 tablespoon at a time. Mix until dough is shaggy. (Note: If dough is dry, add another tablespoon of water until dough is uniform.)

Turn dough out onto clean work surface and knead until dough is firm and smooth. Cover dough with plastic and rest 20 minutes.

Meanwhile in medium bowl, make filling by combining flour, oil and salt.

Uncover dough and knead a few more times. Divide dough into quarters and roll each piece into a smooth ball.

Work with one dough ball at a time, leaving remaining dough covered to keep from drying out. Using rolling pin, roll ball into roughly 6x10-inch rectangle. Cover rectangle with a quarter of the filling paste and sprinkle with an even layer of chopped scallions. ¬¬

Roll dough, starting on one of the longer sides, into a long snake. Gently press down to flatten dough slightly and seal the seam. Press down to remove any air bubbles as best you can, then curl the snake into a spiral. Tuck the end of the snake under the pancake and press down to flatten and seal.

Cover pancake with plastic wrap and repeat with remaining balls of dough.

Working one at a time and keeping remaining pancakes covered, roll out each pancake until about ¼-inch thick.

Heat large cast iron skillet over medium heat. Coat skillet with a thin layer of oil. When oil is shimmering, add a pancake. Cover skillet and cook until golden-brown on the bottom, 3 to 4 minutes. Flip, cover skillet, and cook another 3 to 4 minutes.

Transfer pancake to paper towel-lined plate and repeat with remaining pancakes, adding more oil to the pan.

To serve, cut pancakes into wedges and serve with soy sauce for dipping.