Preheat your oven to 350°F (175°C) and line two baking sheets with parchment paper.
Melt the butter, then whisk in the cocoa powder right away while the butter is still warm.
Let the mixture cool slightly, then stir in both sugars until combined.
Add the eggs and vanilla, whisking until the batter looks glossy.
In a separate bowl, whisk together the flour, baking soda, baking powder, and salt.
Gradually fold the dry ingredients into the wet mixture in 3 additions.
Fold in the chopped chocolate, including the small chocolate shards.
Scoop into 3-tablespoon sized balls and place 2 inches apart on the tray.
Bake for 10-11 minutes until edges are set and centers look slightly underdone.
Cool on the tray for at least 10 minutes before moving.
