Preheat the oven to 350°F (180°C).

In a large mixing bowl, cream together the butter and sugar until fluffy.

Beat in the eggs one at a time, then stir in the vanilla extract.

In a separate bowl, combine the flour, cocoa powder, baking soda, baking powder, and salt.

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

Drop rounded tablespoons of dough onto a parchment-lined baking sheet, leaving about 2 inches between cookies.

Bake for 10-12 minutes, or until the edges are set and the centers are slightly soft.

Allow the cookies to cool on the baking sheet for 5 minutes before transferring them to a wire rack to cool completely.