Preheat the oven to 180 degrees celcius.
Beat the egg yolks with castor sugar until fluffy. If the mixture tends to be thick, add 1 tablespoon of warm water. This will help the mixture turn fluffy again.
With the beater on medium speed add olive oil, bit by bit, like making mayonnaise. Add dry ingredients to the mixture on low speed and beat until all combined. Add the water.
Whip the egg whites until thick, add the sugar and beat until it dissolves.
Pour chocolate mixture into a large bowl and gently but swiftly fold in the egg whites. When well combined pour into a greased 23cm (9 inch) cake tin and bake for one hour or until cooked
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