Preheat the oven to 325ºF. Line an 8x8-inch baking pan with parchment paper. Leave some paper hanging on the sides, it will help to remove the brownies from the pan. Set aside.
In a bowl, sift together the all-purpose flour, cocoa powder, and powdered sugar. Mix in the dark chocolate chips, and salt.
In a large bowl, mix together eggs and granulated sugar with a hand whisk. Then, whisk in olive oil and vanilla extract.
Carefully fold the dry ingredients into the wet ingredients with a spatula until no big lumps of flour remain. Transfer this thick batter to the lined 8x8-inch baking pan.
Bake for 35-40 minutes. Be careful not to overbake the brownies. The top should be crinkly while still being a bit moist inside. Remove from the oven and let cool completely before slicing. Enjoy!