Line the bottom of a springform pan with parchment paper and butter the sides.

Melt the chocolate over low heat in a double boiler, stirring continuously to prevent burning. 

When the chocolate is smooth and melted, add in the olive oil.

Continue stirring over heat and add in 2/3 cup of the sugar. Keep stirring until the sugar is dissolved.

Remove from heat and set aside to cool.

Separate eggs.

Whisk together egg yolks, almond flour, and a few pinches of salt. Combine with the chocolate mixture, stirring until it is smooth and silky.

In a separate bowl, beat the remaining 1/3 cup caster sugar with the egg whites. Whip to stiff peaks using electric beater or stand mixer.

Fold egg whites into chocolate mixture.

Pour the batter into the prepared pan.

Bake for 30-40 minutes, or until a knife comes out clean. Release from pan to prevent excess cracking of the top.