Start this recipe by whipping the egg whites to a stiff peak, then add in the caster sugar and continue mixing till well incorporated. Next, add in the food colouring (I used black) and continue to mix until you have an even colour. It is very important that you add in the food colouring add this stage. In a bowl, mix together the icing sugar and almonds using a spoon, then carefully fold into the whipped egg whites. It should take 30-40 turns in total. It is important that the mixture is soft enough to hold it shape, but doesn’t leave a peak. Place the mixture into a piping bag and pipe the macaroons onto baking sheets lined with non-stick baking paper or mat. Allow to sit for an hour to produce a crust before baking in the oven at 150`c for 12-14 minutes. The macaroons should be firm on top but slightly chewy inside. Remove from the oven and allow to cool down completely before sandwiching the macaroons together with butter cream