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 blended.
Add the eggs, one at a time, mixing well after each addition. Stir in the vanilla extract.
In a separate bowl, sift together the flour, cocoa powder, baking powder, and salt. Gradually add this dry mixture to the wet ingredients, mixing until just combined; avoid overmixing.
Cover the dough with plastic wrap and refrigerate for about 30 minutes to help firm it up.
Once chilled, scoop out small portions of dough (about 1 tablespoon each) and roll them into balls.
Roll each ball in powdered sugar, coating them thoroughly. This creates the 'crinkle' effect when baked.
Place the coated dough balls on the prepared baking sheet, spaced about 2 inches apart.
Bake for 10-12 minutes, or until the edges are set but the centers are still soft.
Allow the cookies to cool on the baking sheet for 5 minutes before transferring to a wire rack to cool completely.
Notes
Arrange the cookies on a colorful platter, dust with extra powdered sugar, and serve with a side of vanilla ice cream for an indulgent treat!