*Pandan juice: Blend 15 g of pandan leaves with 75 g of water, extract 65 g pandan juice.
Combine pao flour, wheat starch, instant yeast and fine sugar for both type of dough in 2 separate mixing bowl, mix well. Add in milk and pandan juice respectively, mix into a dough. (Reminder: Prepare both dough at the same time so that the proofing time is consistent.)
Add in corn oil, mix until well blended. Cover pandan dough with a bowl to prevent it from drying out.
Knead milk dough for 6-7 minutes until the outer is smooth (lightly coat palm with flour if it is sticky), then cover and set aside to rest for 6-7 minutes.
Knead pandan dough for 6-7 minutes until the outer is smooth (lightly coat palm with flour if it is sticky), then cover and set aside to rest for 6-7 minutes.
Put the rested milk dough on parchment paper, roll out into thin flat dough (cover the rolled dough to prevent it from drying).
Put the rested pandan dough on parchment paper, roll out into thin flat dough.
Brush the rolled pandan dough with some water, put rolled milk dough on top of rolled pandan dough, roll out to left and right to help both dough sticking together.
Remove the parchment papers, put the dough on non-stick silicon mat (with milk dough at the bottom), roll out into thinner dough. Flatten the dough at the end where rolling starts, then roll up the thin dough into a rod shape.
Cut into 8 portions using serrated knife (for a nicer cut), put each on a piece of paper.
Bring 500 ml of water to the boil in a steamer, off the heat, then add in 1 Litre of plain water.
Arrange mantou dough in steamer racks, put over warm water, cover and proof for 20 minutes. (Reminder: Using bamboo steamer to steam will prevent condensation water from dripping onto mantou, thus yields a prettier bun.)
After proofing for 20 minutes, turn to high heat until water is boiling (about 3 minutes), then reduce to medium heat and steam for another 15 minutes.