Add 330g all-purpose flour, 2 tsp dried active yeast, 2 tsp salt, 10 g cane sugar, 100ml water and 100ml semi-skimmed milk into a mixing bowl and mix thoroughly using hand until a dough begins to form.
Transfer the dough onto a lightly floured surface and begins the hand-kneading process for 10 minutes until the dough gets more elastic and less sticky.
Then, add 20g unsalted butter to the dough and continue kneading for 10 minutes until the dough is smooth and silky. (Hand kneading refers to - fold the dough, pulling it apart, putting it back together, banging it against the surface and repeating the whole process again.
Place your dough back into a mixing bowl and set aside for proofing purposes for 1 hour for it to rise.
After 1 hour, transfer the dough onto your work surface and punch it down to remove gas bubbles formed by the yeast.
Let it rise for another 15 minutes.
Then, divide the dough into 10 portions and smoothen each one into a round shape.
Let it rise for another 15 minutes.
Press the dough to release additional gas bubble, wrap 1 tbsp red bean paste in the dough and repeat for 10 dough balls.