(click on the text to highlight each stage):
- Preheat the oven to 180°C/160°C Fan/ Gas 4. Grease and flour a 20 cm spring form cake tin. Cream the butter with 110g Golden Caster sugar until light and creamy.
- Whisk in the egg yolk.
- Sift together the flour and cornflour and fold into the mixture.
- Whisk the egg whites until they form soft peaks and whisk in the remaining sugar.
- Gently fold half this meringue into the cake mixture until incorporated, then fold in the other half with the rosemary.
- Spoon into the prepared cake tin and bake for 30-35 minutes.
- Cool in the tin for 15 minutes then turn out onto a wire rack to become cold.
- Dust the top of the cake with Golden Icing sugar and decorate with sprigs of rosemary.