Preheat the oven to 180°C (350°F) and line a baking sheet with parchment paper.

Beat the softened butter and brown sugar until creamy.

Add the egg and mix until smooth.

Gradually fold in the melted dark chocolate.

Sift together flour, cocoa powder, and baking powder, then mix into the wet ingredients until combined.

Stir in the chocolate chips.

Scoop small portions of dough onto the prepared baking sheet.

Bake for 8-10 minutes until the edges are set but the centers remain soft.

Let cool on the baking sheet for 5 minutes, then transfer to a wire rack.