Preheat your oven to 350°F (175°C) and line a baking sheet with parchment paper.

In a large mixing bowl, combine the granulated sugar, brown sugar, and vegetable oil. Mix until well combined.

Add the eggs one at a time, mixing well after each addition. Stir in the vanilla extract.

In a separate bowl, whisk together the flour, cocoa powder, baking powder, and salt. Gradually add this dry mixture to the wet ingredients, mixing until just combined.

Cover the dough with plastic wrap and refrigerate for at least 30 minutes to firm up.

Once chilled, use a cookie scoop or tablespoon to portion out the dough. Roll each portion into a ball, then roll the balls in powdered sugar until fully coated.

Place the coated dough balls on the prepared baking sheet, leaving about 2 inches of space between each cookie.

Bake for 10-12 minutes, or until the edges are set but the centers are still soft. Let them cool on the baking sheet for a few minutes before transferring to a wire rack to cool completely.