Preheat oven to 180ºC (356ºF) and line a baking tray with parchment paper, set aside.
Beat butter until soft, add icing sugar and zests and beat together until light and fluffy.
Fold through flour and baking powder. Using your hands, gently bring the mixture into a soft dough. Do not overmix.
Move to a floured board.
Roll out to 1cm thick, using a medium sized scalloped round cookie cutter, cut into rounds and repeat with remaining scraps until all used up.
Place shortbreads on prepared tray and set in refrigerator for 15 minutes.
Remove from the fridge and bake for 9-12 minutes or until pale and crisp.
Allow shortbreads to cool on the tray for 5 minutes then transfer to a wire rack to cool completely.
In a mixing bowl, combine 1 cup of icing sugar, lime and lemon juice and coconut water. Mix well until smooth.
Add the extra 1/4 cup of icing sugar until thick and smooth. Add more icing sugar for desired consistency.
Spread icing on one half of each shortbread.
Optional: sprinkle lime and lemon zest on the icing for extra punch!
Serve and Enjoy!
Store in an airtight container for 1 week – 10 days.