In a large bowl, whisk together the flour, cocoa powder, baking powder, and kosher salt until evenly combined.

Melt the dark chocolate in 15-second intervals, stirring after each interval until smooth. Let it cool slightly.

In a separate mixing bowl, cream together the butter, brown sugar, and granulated sugar until light and fluffy.

Add the eggs one at a time, mixing well after each addition. Scrape down the sides of the bowl as needed.

Add the vanilla extract with the final egg and mix until combined.

Pour the melted chocolate into the butter mixture and stir until fully incorporated.

Gradually add the dry ingredients in three additions, mixing just until combined.

Fold in the chocolate chips until evenly distributed.

Scoop the dough into cookie portions and place on a tray.

Chill the dough for at least 30 minutes for thicker, chewier Double Chocolate Chip Cookies.

Preheat the oven to 350°F (175°C) convection.

Arrange the dough balls on parchment-lined baking sheets, leaving space between each cookie.

Bake for 7–8 minutes, or until the tops appear cracked and matte.

Sprinkle lightly with Maldon salt if desired.

Allow the cookies to cool completely before serving.