Preheat the oven to 350°F (175°C).
In a medium bowl, whisk together the flour, baking powder, baking soda, and salt.
In a large mixing bowl, cream together the softened butter and granulated sugar until light and fluffy.
Add in the egg, vanilla extract, and food coloring; mix until well combined.
Gradually add the dry ingredients to the wet mixture, mixing until just combined.
Scoop tablespoon-sized balls of dough onto a lined baking sheet.
Bake for 10-12 minutes or until the edges are lightly golden.
Allow the cookies to cool on the baking sheet for 5 minutes before transferring them to a wire rack.
Prepare the icing by mixing the powdered sugar and milk until smooth.
Decorate the cooled cookies with icing and allow to set.
