1. Pre-heat oven with a fan to 160°C and set to convection (fan) setting.
2. Sift Prima Hong Kong and Superfine Wholegrain Flour together and set aside.
3. Cream butter and icing sugar until light and slightly fluffy.
4. Add in flour mixture until combined.
5. Add in eggs and vanilla essence until a dough ball is formed.
6. Shape the dough into a flat rectangular shape. Cling wrap and chill in the fridge for at least 30 minutes.
7. Repeat steps 2 to 6 for the rose-flavoured dough with the additional steps of creaming butter with pink colouring before adding icing sugar, and adding rose flavour to the egg.
8. Divide the dough into 3 equal portions. Roll the dough to 1 cm thickness and shape it into a rectangle. Stack 3 layers of dough on top of each other in alternating colours and gently press them down to ensure the dough sticks together. Cling wrap and chill in the fridge for 20 minutes.
9. Slice the dough length-wise into strips with equal width of about 1 cm each. Arrange the dough strips in alternating colours to create a checkerboard pattern. Use egg white wash to seal the pieces together. Cling wrap and chill the dough in the fridge for 20 minutes.
10. Slice the dough into equal thickness of about 0.5-0.7 cm. Bake at 160°C for about 15 minutes.