Preheat oven to 150ºC conventional (130ºC fan forced). Line 2 trays with baking paper.
Beat egg whites in small bowl with electric mixer until soft peaks form. Add caster sugar, a tablespoon at a time, whisking until mixture is thick and glossy (2-3 mins), and add food colouring. Sift icing sugar and almond meal 3 times through coarse sieve. In 2 batches, fold in icing sugar/almond mixture and lemon rind into egg white base.
Fill piping bag fitted with 2cm plain tube. Pipe 4cm rounds allowing space around each macaron. Tap trays on bench so macarons spread slightly. Stand for 30 mins on bench to form a crust.