Pre-heat oven to 180°C. Grease and dust with flour an 8-inch round springform tin.
Beat the butter and raw sugar until creamy. Add the egg yolks and beat for a minute. Add the flour, milk, vanilla, rind and juice. Beat until combined and smooth. Spoon batter into prepared tin.
Beat the whites of the eggs to a stiff froth. Add 1 tablespoon of caster sugar and beat again until foamy. Fold through the coconut. Spread this mixture over the top of the cake batter and bake for approximately 45 minutes until golden and cooked through.