In a large bowl, whisk together the flour, cacao powder, baking powder, baking soda, and sea salt. Set aside.
Using a hand mixer, mix together the sugar and extra virgin olive oil for 1 minute in a separate bowl.
Add in the egg into the sugar mixture and whisk for another 30 seconds. Add in the milk and vanilla extract, whisk until well combined.
Sift the flour mixture into the egg mixture. Mix together until evenly distributed.
Form the batter into a rectangle-form and cover with plastic wrap. Chill in the refrigerator for 1 hour.
Preheat oven to 325F.
Roll out the dough to be 1/8" thick. Using a circular cookie cutter, or another kitchen item, make the circles about 2" thick in diameter.
Place the cut-out dough pieces on a pan with parchment paper. Bake for 15 minutes.
Allow the cookies to cool completely.