Preheat the oven to 350°F (175°C) and line a baking sheet with parchment paper.
Cream together butter, granulated sugar, and brown sugar in a large bowl until light and fluffy.
Add eggs, one at a time, and the vanilla. Mix until fully incorporated.
In a separate bowl, whisk together flour, cocoa powder, baking soda, and salt.
Gradually add the dry ingredients to the wet ingredients, mixing until just combined.
Fold in 2 cups of semi-sweet chocolate chips.
Scoop the cookie dough using a tablespoon or cookie scoop and place it on the prepared baking sheet about 2 inches apart.
Press the extra ½ cup of chocolate chips on top of each cookie dough ball.
Bake for 9-11 minutes until the edges are set but the centers are still soft. The cookies will continue to bake on the sheet.
Remove from the oven and let the cookies cool on the baking sheet for 5 minutes before transferring them to a wire rack to cool completely.