Cut and blend overripe bananas finely.

Add salt, sugar, vanilla extract, oil to a bowl of egg yolks and whisk thoroughly.

Sift self raising flour and corn flour into the bowl.

Add blended bananas and mix well.

In a separate bowl, whisk egg white and add sugar (in 2 batches) and lemon juice. Whisk until it reaches a firm peak.

Add ⅓ of the meringue to the banana flour mixture first and mix.

Pour the mixture into the rest of the meringue and fold gently.

Line an 8 inch round pan with baking paper and slowly pour in the batter.

Tap the pan on a hard surface to remove large air bubbles.

Arrange walnuts on the top in any way you like.

Prepare a larger pan filled with hot water (about 1 inch level) for the pan with batter to sit in.

Bake in a preheated oven (lowest rack) at 150C for 20 mins. Then lower the temperature to 140C and bake for another 50 to 60 mins until golden brown. Cake is done when a skewer inserted in the centre comes out clean.

Remove cake from the oven and gently press the top of the cake and it should bounce back.

Unmould cake and let it cool on a wire rack.