In a bowl whisk together the flour, baking soda and salt until well combined.

In a large mixing bowl, whisk the olive oil, brown sugar, granulated sugar, espresso powder and vanilla extract until well combined. Whisk in the egg and egg yolk until smooth and well combined.

Stir the dry ingredients into the wet until just combined. I like to do this about ½ of the dry ingredients at a time. Fold in most of the chopped chocolate or chocolate chips. Reserve about ½ cup (85 g) for topping the cookies right before baking.

Cover the cookies with plastic wrap and transfer to the fridge to chill for 30 minutes or up to overnight. About 30 minutes before baking the cookies, preheat the oven to 375 F (190 C). Line a large baking sheet with parchment paper.

Using a large cookie scoop (3 tablespoons, 45 ml), scoop the olive oil chocolate chip cookie dough and place the cookie dough balls onto the lined baking sheet about 3 inches (8 cm) apart. Top with the reserved ½ cup (85 g) of chocolate chips or chunks.

Bake for 12 - 14 minutes or until the edges of the cookies are set and the centers are slightly puffed. Cool the chewy olive oil cookies on the baking sheet for 5 minutes. If the cookies transfer easily at 5 minutes, then transfer to a cooling rack to cool completely to room temperature. If not, allow them to cool for an additional 5 minutes on the warm baking sheet, transfer to the cooling rack and enjoy!