Preheat oven to 160C. Grease and line the base of a 24 cm fluted tart pan (for fluted edges) or a 24 cm round springform pan for a smooth finish.
In a mixing bowl combine the flour, icing sugar, almond meal, coconut and zest. Use your hands or a whisk to ensure the dry ingredients are mixed well and evenly dispersed.
Add egg whites and stir to combine.
Add melted butter and mix until well incorporated.
Transfer the mixture to the prepared pan. Bake for 35-40 minutes or until golden and a skewer inserted in the centre of the cake comes out clean.
Remove from the oven and place on a cooling rack. Allow the cake to sit for 15 minutes before removing it from the pan.