Whisk the flour, baking soda and baking powder together,keep aside.
In a mixing bowl cream the butter and sugar till fluffy with a hand mixer.
Add the vanilla and egg,beat.
Add the dry ingredients gradually and mix.
Add the milk and form into a soft dough,it should be soft and not wet.
Knead the dough on a floured surface and if it’s wet adjust it with a little flour added to it and if it’s dry add a little milk.
Form into a ball and cover with a cling film and chill it for an hour if chilling the dough, otherwise roll it out straightaway.
After removing from the fridge wait for a few minutes for the dough to soften so that it’s easy to roll it out.
Roll the dough on a floured surface and with holiday theme cookie cutters cut them out and lay them on a cookie tray with parchment paper.
Bake them in a preheated oven at 180 deg C for 8-10 mins.If you want them crisp you can bake it a little longer .I like them chewy in the middle and crisp at the sides.
For the icing ,mix the icing Sugar with the milk and vanilla and make sure the mixture is not flowy,adjust the milk and icing sugar as needed.
Divide the mix according to the colours you want and transfer them to piping bags,can use zip locks as piping bags.
While cutting holes in the piping bags make sure the hole isn’t too big or it will be difficult to make outlines.
Decorate the cookies with piping the outlines first and then filling them and spread with a butter knife.
Decorate with sprinkles and let them set overnight before storing.