Whisk butter and icing sugar together till fluffy.
Add all the dry ingredients, egg and vanilla extract. Knead into a dough.
Divide the dough into two. Place on a waxed baking paper and roll to about 0.5cm thickness. Keep in the fridge for 2 hours or till it is slightly harden.
Preheat oven to 150°C 20mins before you prepare the cookies.
Cut the cookie with a cookie cutter. Bake for 15-20 minutes.
Let the cookies cool overnight.
Prepare the Icing
Whisk egg and icing sugar in a bowl until thicken.
Add lemon juice to thin out the texture according to what you like. Do add by ½ tsp each time.
Divide into portions and add food colouring of choice, depending on your decoration of choice (e.g. black colour for face and arms, orange colour for nose etc).
Pipe onto the cookie with a piping bag. You can shape thin lines with a toothpick.
Preheat oven at 60°C on broil setting. After piping, place them into the oven and dry for 20 mins. This is also to pasteurize the egg whites.
You can decorate with other decorations such as marshmallows (head) and M&M’s or Skittles candies for the buttons.