Preheat your oven to 350°F (175°C).

In a large bowl, cream together the granulated sugar, brown sugar, and softened butter until smooth.

Beat in the egg and vanilla extract until well combined.

In another bowl, whisk together the flour, cocoa powder, baking soda, and salt.

Gradually add the dry ingredients to the wet ingredients, mixing until just combined.

Fold in the chocolate chips until evenly distributed.

Scoop tablespoon-sized portions of dough onto a baking sheet lined with parchment paper.

Bake for 10-12 minutes, until the edges are set but the centers are still soft.

Remove from the oven and let cool on the baking sheet for 5 minutes before transferring to a wire rack.

Enjoy your delicious chocolate cookies fresh or stored for later!