To prepare the batter for the fresh flat pho rice noodle sheets, first soak the 4 cups of white rice in a large plastic bowl of water overnight.
The next day, drain the water from the rice then thoroughly wash the rice in water. Do this at least three times, properly draining the water each time until the water is clear. Ensure the water is completely drained from the rice.
Put 1 cup of white rice, 2 cups of water, and a pinch of salt in a blender and blend for 10-15 minutes.
Remove the mixture from the blender and put it in a bowl and leave to rest for one hour.
Repeat with the remaining rice, 1 cup of rice to 2 cups of water at a time. Leave each mixture to rest for an hour.
Spread a little vegetable oil onto a flat tray or plate in preparation for the steamed rice noodle sheets.
To make the flat rice noodle sheets, cover a pot of boiling water with a thin piece of cotton, pulled tautly over the pot and secured with string.
Using a large spoon (should hold two tablespoons of batter), pour the rice noodle batter onto the cotton, using the bottom of the spoon to move the batter around to form a thin circle-shaped layer that evenly and completely covers the cotton.
Steam the batter for one minute until you have a firm flat rice noodle sheet.
Use a bamboo stick to lift the rice batter from the cotton, by sliding it between the rice noodle sheet and cotton at the centre. Place it onto the oiled plate.
Repeat, stacking the flat rice noodle sheets on top of each other as you go. They shouldn’t stick together but if concerned spread a little vegetable oil onto each sheet.
Allow to cool