In a medium bowl, sift together cocoa powder, granulated sugar, flour, baking powder, ground ginger and salt. Set aside.
Using a stand mixer, add vegetable oil, eggs, and vanilla extract. Quickly mix on low to combine.
Keeping speed on low, add ⅓ of the dry ingredients and add it to the wet ingredients, mixing for 30 seconds to 1 minute. Continue adding the rest of the dry ingredients until cookie batter is thoroughly mixed. Batter will be dark and sticky.
Cover and chill cookie dough for at least 1 hour or up to overnight.
Preheat oven to 350 degrees and line a baking sheet with parchment paper.
Place powdered sugar in a shallow bowl and set aside.
Scoop 2-3 heaping tablespoons of cookie dough and roll it into a ball. Drop ball in powdered sugar and toss to coat completely. Place sugar coated cookie ball on the prepared baking sheet. Repeat this step until all the cookie dough batter is used, spacing cookies 2 inches apart.
Bake for 10-13 minutes or until tops of cookies have a crackled appearance.
Let cookies cook on the baking sheet for 5 minutes before transferring to a wire rack to cool completely.
Store cookies in a sealed container at room temperature for up to 4 days.
Cookies will look overbaked when you take them out of the oven, they will continue to cook and solidify as they cool.