Put the flour in a large bowl (I use a wooden salad bowl). Add the boiling water and stir until a shaggy dough forms. Gather the scraps together, pressing and kneading to form a dough ball. Knead the dough in the bowl or on a work surface, floured if necessary, until soft but not very sticky, about 8 minutes. The dough should be light and not very resilient; when you stick your finger in, a slight indentation should remain. Cover the dough with a damp towel and let rest for 15 minutes. Knead for another 3 minutes.
Put the sesame oil in a small bowl. Shape the dough into an even cylinder. Cut the cylinder into 8 equal pieces. Use a rolling pin to roll one piece into a 6-inch round. Brush the top with the sesame oil and then sprinkle on about 1/4 tsp. salt, about 1/2 Tbs. each scallions and cilantro, and about 2 tsp. toasted sesame seeds. Roll up the pancake tightly, stretching to lengthen it slightly. Tie the ends of the cylinder around as if you were forming a knot. Flatten the knotted ball on a lightly floured surface with your palm and then roll it out again into a 6-inch round. Repeat with the remaining pieces of dough.
Roll out a piece of the divided dough into a 6-inch round and brush with sesame oil. Sprinkle liberally with salt, scallions cilantro and toasted sesame seeds.
Roll up the round very tightly, as you would a cigar, stretching the dough as you roll to lengthen it a bit.
Tie the ends around as if you were forming a knot, but stop before one end protrudes through the center hole.
Flatten the knot with your palm and then roll it out again into a 6-inch round. This creates layers of dough with the herbs pressed right in.
In a large heavy skillet, pour enough peanut oil to come to a depth of 1/4 inch. Heat the oil to 380°F (a rice noodle will puff into a curlicue within 3 seconds or a cube of bread will turn golden in 15 seconds). Fry one or two pancakes at a time until both sides are golden and slightly crisp, 2-1/2 to 3 minutes per side. Drain on paper towels and sprinkle immediately with coarse salt. Serve hot.
Scallion pancakes cook to golden crispness in about 5 minutes. A sprinkling of coarse salt and they're ready to serve.