Preheat the oven to 170°C.
Ensure the butter is at room temperature, then cream it with two-thirds of a cup of icing sugar until well combined.
Add one egg white, two teaspoons of vanilla extract, and a pinch of salt. Mix thoroughly.
Gradually add 1/4 cup of cornstarch followed by one cup of all-purpose flour, mixing just enough to combine the dough without making it too stiff.
Using a piping bag with a nozzle, shape the cookies into balls or any desired shapes and place them on a baking tray.
Bake for 15 minutes until golden brown but still slightly soft in the middle.
Allow the cookies to cool before decorating them with food coloring and colorful rice if desired.