Mix Dry Ingredients: In a medium bowl, whisk together the flour, cocoa powder, baking powder, and salt until well combined.

Mix Wet Ingredients: In a large mixing bowl, whisk together the granulated sugar and vegetable oil until smooth. Add the eggs, one at a time, beating well after each addition. Stir in the vanilla extract.

Combine Wet and Dry Ingredients: Gradually add the dry ingredients to the wet ingredients, mixing until just combined. The dough will be thick and sticky.

Chill the Dough: Cover the dough with plastic wrap and refrigerate for at least 2 hours or until firm. This step is essential for achieving the crinkle effect on the cookies.

Preheat Oven: Preheat your oven to 350°F (175°C). Line a baking sheet with parchment paper.

Form the Cookies: Scoop out tablespoon-sized portions of dough and roll them into balls. Roll each ball in powdered sugar until completely coated.

Bake: Place the coated dough balls on the prepared baking sheet, spacing them about 2 inches apart. Bake in the preheated oven for 10-12 minutes, or until the cookies are set around the edges but still slightly soft in the center.

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