Preheat oven to 350°F. Line and grease a 9 x 13-inch pan with parchment paper.

In a medium bowl, whisk together the flour, baking powder and fine sea salt. Set aside.

In bowl of stand mixer, add the brown and white sugars, and melted coconut oil. Beat until well mixed. Add the milk and vanilla and mix until smooth. Add the reserved flour mixture and beat until everything is creamed together. Stir in the chocolate chips, mixing on low.

Evenly press the cookie dough into the prepared pan. Lightly sprinkle the top with Maldon sea salt.

Bake in the preheated oven for 20 to 25 minutes, or until center is almost firm to the touch and just leaves a little dent in the top, and the edges are lightly golden. Let bars cool completely in pan before cutting into squares.