4 large Seville oranges
225g/8oz plain flour
175g/6oz caster sugar
225g/8oz caster sugar
75g/3oz cornflour
25²µ/ΒΎ΄Η³ϊ icing sugar
100²µ/3Β½΄Η³ϊ butter
5 egg whites
1 egg yolk
4 egg yolks