Whip your egg whites and white caster sugar to stiff glossy peaks.
Sift the powdered sugar and almond flour into the egg white mixture and fold the dry ingredients in, until the consistency is glossy and smooth – and flows like lava.
When adding the food coloring, slightly under-mix the batter and then stir in the color.
Fill your piping bags and have fun piping your cookies!
Allow the unbaked cookies to sit, uncovered, at room temperature for 45 minutes – 1 hour until the tops are no longer sticky and have formed “skins.”
Bake for 20 minutes at 300*F, until the cookies have puffed and a “foot” has formed. Allow to cool before sandwiching with buttercream frosting.