Sift flours, salt, baking powder, baking soda and gingerbread spice mixture together into a big bowl.
Add brown sugar and mix well.
Add the butter cubes and rub it into the flour using your finger tips till it resembles bread crumbs.
Add the molasses or any substitute you're using and the milk.
Bring the mixture together into a the dough till it gets wet. Do not over mix the dough.
Divide the dough into two parts. Shape each part into a round disc.
Cover each part with cling film and put it in the freezer.
In the meantime prepare the baking tray. You can line it with parchment paper or lightly grease it with butter.
Preheat the oven to 160ºC.
Put the sugar and icing sugar in two different bowls.
Take out both the dough parts from the freezer. Put one part in the fridge till required.
Using a tablespoon, scoop up the dough and roll it into a ball. Remember do not roll it too much otherwise the dough will become warm.
Roll the ball in the sugar and then in the icing sugar.
Place it on the baking tray.
Repeat steps 11 to 13 with the rest of the dough.
Place the balls 1 inch apart.
Put the tray in the oven and let the cookies bake for 12-15 minutes.
Remove the tray from the oven.
Let the cookies cool down for 2-3 minutes on the tray.
Put the cookies on a wire rack to cool down completely.
Store in an airtight container.
Take out the other part of the dough from the fridge and bake the cookies.