In a large bowl, mix the flour with salt, then add the hot water. Using your hands, keep mixing the dough then knead it until you get a smooth dough ball. What hot water dough is "kill" the flour, which helps create the layers that are flaky and chewy rather than soft and fluffy. Add more flour and cold water as needed. Lightly brush the dough with oil, cover it and let it rest for half an hour (or overnight in the fridge).
Divide the dough into 4 pieces. This portion will make four 7-inch pancakes.
Roll out the dough into a rectangle about 3mm (⅛" inch) thick. Brush with oil (or sesame oil), and sprinkle with thinly sliced scallions and seasonings if using.
Roll the full length of the dough to create a long sausage shape, then coil into pinwheels tucking the loose end underneath.
Flatten each pinwheel using the palm of your hands, and you can even roll it out using a rolling pin into a 7-inch pancake. Heat oil in a flat bottomed pan, and fry for 2-3 minutes on each side.
Keep flipping the pancake to ensure that it does not burn. Drain on kitchen paper towels, cut into quarters, and serve.
Freeze the pancakes between sheets of parchment paper, when ready to cook, take them out of the freezer and pan-fry them with a little bit of oil (no need to thaw first).
When buying sesame oil, check that the label says 'pure sesame oil' rather than 'blended sesame oil'.
You can either make 4 7-inch pancakes or 8 smaller ones.
Fry in more oil for restaurant-quality scallion pancakes.
For the dipping sauce: Mix 2 tablespoons of soy sauce with 1 teaspoon of honey, 2 teaspoons of vinegar, 1 teaspoon of sesame oil, 1 clove of garlic, and about 1 teaspoon of grated ginger.