Prepare a large mixing bowl. Dig a small hole in center and then pour the hot water in. Wait for 10 minutes and then stir in the cold water and vegetable oil. Grasp everything to form a ball, cover and rest for 5 minutes and then knead until very smooth (around 3-5 minutes ). The dough should be quite soft. Cover the rest for 20 to 30 minutes.
Roll up the circle into a cylinder. And further roll into the shape of a snail. Cover with wet cloth and rest for 10 to 15 minutes.Roll the snail out to another thin circle.
Brush some cooking oil on the pan and move the circle into the pan. Use middle fire to pan-fry until the surface becomes brown around 2-3 minutes. And turn over to fry for another 1 to 2 minutes. Use a spatula to press the circle from time and time especially the central part to ensure the circle is evenly fried.
Remove the circle out and cut into wedges.