Preheat oven to 180 C (350 F) standard / 160 C (320 F) fan-forced. Line an 8-inch square pan with baking or parchment paper.
In a large mixing bowl, add olive oil, vanilla and sugars and mix briefly.
In a separate bowl, add eggs and whisk with a fork for approximately 30 seconds or until combined.
Add eggs to sugar mixture, along with cocoa powder, flour and chocolate chips. Gently mix with a spoon or spatula to combine. Pour into prepared tin.
Bake for approximately 28-30 minutes or until a knife inserted in the middle comes out clean. Leave to cool slightly before removing from pan. They will firm up as they cool. Serve with ice cream or whipped cream.
