1

Preheat oven to 180°C. Lightly spray a 23cm (base measurement) round springform tin with oil. Line base and side with baking paper.

2

Using electric beaters, beat egg whites and ¼ cup (55g) white sugar in a large bowl until soft peaks form. Set aside.

3

Using electric beaters, beat egg yolks and remaining white sugar in another medium bowl until thick and pale. Continue beating while gradually adding olive oil. Add yoghurt, both lemon and orange rind and juice, and a pinch of salt and beat to combine. At low speed, add flour and beat just until combined. Gently fold egg white mixture into flour mixture, in 3 additions, until just combined.

4

Spoon mixture into prepared tin and smooth surface with the back of a spoon. Bake for 45–50 minutes or until a skewer inserted into the centre comes out clean. Set cake aside in tin on a wire rack to cool completely before turning out onto a plate. Serve cake dusted with icing sugar.