Grease and line a small rectangular slice tray (approx 16cm X 26cm) with baking paper and set aside.
Place the icing sugar and cream of tartar into the Thermomix bowl and mix on Speed 9 for 10 seconds.
Add the coconut and condensed milk to the bowl and mix on Speed 4 for 10 seconds. Scrape down the sides of the bowl and repeat for a further 5 seconds.
Press half of the mixture firmly into the prepared tray.
Add the food colouring to the Thermomix bowl and mix on Speed 4 for 10 seconds - use the spatula to help mix the food colouring completely through the mixture.
Press the pink mixture on top of the white layer and place into the fridge to set.
Cut into pieces.