1.Preheat oven to 150ºC/130ºC fan-forced. Grease four oven trays; line with baking paper.
2.Beat egg whites in small bowl with electric mixer until soft peaks form; add caster sugar, beating until dissolved between additions. Transfer mixture to large bowl. Fold in sifted icing sugar, ground almonds and coconut, in two batches.
3.Spoon mixture into large piping bag fitted with 1.5cm plain tube. Pipe 4cm rounds, about 2cm apart, onto trays. Tap trays on bench to help macaroons spread slightly. Dust macarons with extra sifted icing sugar; stand 15 minutes.
4.Meanwhile, make lemon cream by beating cream sugar and rind with electric mixer until soft peaks form.
5.Bake macarons 20 minutes. Stand macarons on trays 5 minutes; transfer to wire rack to cool.
6.Sandwich macarons with lemon cream just before serving.