Preheat oven to 350F.
Line baking sheets with silicone mats, parchment paper or lightly spray with cookie spray. Set aside.
Whisk together the flour, cocoa powder, baking soda and salt in a small bowl. Set aside.
Using an electric mixture, cream the butter and sugars until light and fluffy.
Add the eggs, one at a time, beating well after each addition.
Add the vanilla.
Gradually add the dry ingredients until just combined.
Fold in the semisweet and bittersweet chocolate chips.
Using a 1 1/2 tablespoon cookie scoop, drop the cookie batter onto cookie sheets, placing the cookies about 2-inches apart.
Bake for 12 minutes, or until the centers are set.
Let the cookies cool for about 5-minutes on the baking sheet then place on cooling racks to cool completely.