Preheat the oven to 350°F (175°C) and line baking sheets with parchment paper.

In a mixing bowl, combine the granulated sugar, brown sugar, and softened butter. Use a whisk to cream the mixture until light and fluffy.

Add the eggs one at a time, whisking well after each addition. Then stir in the vanilla extract.

In a separate bowl, sift together the all-purpose flour, cocoa powder, baking powder, and salt.

Gradually add the dry ingredients to the wet mixture, mixing until just combined. The dough will be thick.

Refrigerate the cookie dough for about 15 minutes to help it firm up.

Using a cookie scoop or tablespoon, portion out the dough and roll it into balls. Then roll each ball in powdered sugar until fully coated.

Place the coated dough balls on the prepared baking sheets, spacing them about 2 inches apart.

Bake in the preheated oven for 10-12 minutes, or until the edges are set and the tops are crinkled.

Remove from the oven and let cool on the baking sheets for a few minutes before transferring to a wire rack to cool completely.

For an extra rich flavor, consider adding chocolate chips to the dough.

Store the cookies in an airtight container at room temperature for up to a week.