Mix salt with all purpose flour in a large mixing bowl. Make a small hole in the centre and then pour the hot water in. Wait for 10 minutes and then stir in the cold water and vegetable oil. Form the dough into a ball, cover and rest for 5 minutes.
Knead until very smooth (around 3-5 minutes ). The dough should be quite soft. Cover and rest for 20 to 30 minutes.After resting, the dough should be quite easy to roll out. Divide the large dough into 4 pieces and roll each piece into a large round circle (18-20cm). Brush each one with some sesame oil, sprinkle with Chinese five spice power and chopped scallion (leaving 1 cm without onions around the edge). Roll up the circle into a cylinder.
Roll the cylinder into the shape of a snail. Cover with wet cloth and rest for 10 to 15 minutes.
Roll out the pancake to large around circle. Be gentle and use your hands as much as possible because a rolling pin will puncture the dough. It will be around 18cm in size.
Brush a frying pan with oil. Pan-fry on medium temperature until the surface becomes brown around 2-3 minutes. Turn over to fry the other side. Use a spatula to press the circle from time and time especially the central part to ensure the circle is evenly fried.
Combine ingredients for dipping sauce. Cut pancakes into 6 triangles and enjoy!