Whisk together the olive oil, brown sugar, and granulated sugar until well combined.
Whisk in the egg, egg yolk, and vanilla until well combined.
Fold in the flour, baking soda, salt, and chopped chocolate until just combined.
Cover the bowl and chill it in the fridge for 30-45 minutes or until the dough is firm.
Preheat the oven to 350 F/180 C. Line two baking trays with parchment paper.
Use a large (roughly 3 tablespoons) cookie scoop to scoop 13 dough balls.
Space them 3 inches apart on the prepared baking tray. Add more chopped chocolate to the tops if desired.
Then place one tray back in the fridge while the other one is baking.
Bake the ttrays one at a time for 10-12 minutes or until the edges are barely golden brown but the center is still gooey.
Let the tray cool on a wire rack then sprinkle with flaky salt and enjoy!