In a large mixing bowl, whisk together cocoa powder, sugar, and oil until smooth. Add eggs one at a time, beating well after each. Stir in vanilla.
In a separate bowl, whisk together flour, baking powder, and salt. Gradually mix dry ingredients into the wet ingredients until a soft, sticky dough forms.
Scoop tablespoon-sized balls of dough, roll them in powdered sugar until fully coated, and place them on a parchment-lined baking sheet. Bake at 350°F for 10–12 minutes or until the edges are set and tops are crackled.