Preheat your oven to 350°F (175°C). Line a baking sheet with parchment paper or a silicone baking mat.

1. In a medium bowl, whisk together the flour, cocoa powder, baking soda, and salt. Set aside.
2. In a large bowl, cream together the softened butter, granulated sugar, and brown sugar until light and fluffy, about 2-3 minutes.
3. Beat in the egg and vanilla extract until fully combined.
4. Add the melted dark chocolate to the butter mixture and stir until smooth.
5. Gradually add the dry ingredients to the wet ingredients, mixing until just combined.
6. Stir in the chocolate chips until evenly distributed throughout the dough.
7. Use a cookie scoop or spoon to drop rounded tablespoons of dough onto the prepared baking sheet, spacing them about 2 inches apart.
8. Bake for 10-12 minutes, or until the edges are set and the centers look slightly soft.
9. Allow the cookies to cool on the baking sheet for 5 minutes before transferring them to a wire rack to cool completely.