Separate egg yolks from egg whites.

Sift self raising flour (or cake flour plus baking powder).

Grate orange zest and squeeze out the orange juice.

Beat egg yolks, add caster sugar and continue beating until pale yellow.

Add cooking oil and beat until mixture looks like mayonnaise.

Add vanilla extract, salt and continue beating. Add orange zest and beat briefly. Add orange juice and beat until well mixed.

Add half of the sifted self raising flour and beat gently at low speed (#1). Continue mixing in remaining flour..

In another mixing bowl, whisk egg whites until foamy.

Add half of the caster sugar and continue whisking. Add remaining sugar and whisk until it reaches firm peaks.

Add meringue to the egg mixture in 2 batches and fold gently.

Arrange three small (15 cm) chiffon baking pans on a tray and spoon the cake batter into the chiffon pans. Do not grease grease the pans.

Tap the baking pans on the table firmly to release trapped air bubbles. Also run a skewer or chopstick through the batter to help release bubbles.

Bake in a preheated oven at 170 C for 15 to 20 minutes.

Rotate the pans and bake for another 20 minutes. Cover top with baking paper (if necessary) to prevent overheating.

Remove pans from the oven and test by poking with a skewer. If it comes out clean then cake is done.

Invert the pans immediately after and leave them to cool down.

Unmould the cakes by running a thin spatula or bread knife round the sides to separate the cake from the pan.

Invert the pan and press out the base.

Run a thin spatula along the base to remove the cake.