Preheat your oven to 350°F (175°C).

Line a baking sheet with parchment paper.

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

In a separate bowl, use an electric mixer to cream the softened butter and granulated sugar until light and fluffy.

Beat in the egg and vanilla extract until fully combined.

Gradually mix in the dry ingredients until just combined.

Use a tablespoon or cookie scoop to drop dough onto the prepared baking sheet.

Bake in the preheated oven for about 10 minutes.

Let the cookies cool on a wire rack.