Preheat oven to 350°F (175°C). Line two baking sheets with parchment paper.

In a medium bowl, whisk together cocoa powder, sugar, melted butter, and oil until smooth.

Add egg and vanilla; mix until thick and glossy.

Add flour, baking powder, and salt. Stir gently until just combined (do not overmix).

Fold in chocolate chips.

Scoop 1.5 tablespoons of dough per cookie, place 2 inches apart on sheets. Flatten slightly if desired.

Bake 10–12 minutes; edges should be set but centers still soft.

Cool on sheet for 10 minutes, then transfer to wire rack to cool completely.