Start by mixing the granulated sugar, brown sugar, and vegetable oil in the bowl of your stand mixer (or use a hand mixer if that’s what you have). 

Blend everything together until it’s smooth and creamy. Add the eggs individually, ensuring each one is completely mixed in before adding the next. Don’t forget the vanilla extract! Mix until everything is smooth and velvety.

Next, it's time to add the dry ingredients. Slowly incorporate the dark cocoa powder, all-purpose flour, baking powder, and salt into the bowl. 

Start mixing slowly to avoid a cocoa cloud, then increase the speed until everything comes together into a thick dough. Don’t worry if the dough feels a little stiff, that’s perfect!

Now, chill the dough! This is an important step to get those perfect crinkles. Place the dough in an airtight container and refrigerate for at least 4 hours, or overnight if you have the time.

As the dough chills, preheat your oven to 350°F (175°C) and line a baking sheet with parchment paper. This will help your cookies bake evenly and come off the sheet easily.

When your dough is chilled, grab a tablespoon (or a 1 ½ tablespoon scoop) to portion out the dough. Shape each piece into a ball, then roll them thoroughly in powdered sugar. This is what gives the cookies their signature crinkled look and a sweet, crunchy exterior.

Arrange the dough balls on the prepared baking sheet, ensuring there’s a 2-inch gap between each. 

Put them in the preheated oven and bake for 10 to 11 minutes. As they bake, you’ll see the crinkles start to form. Don’t be worried if they seem soft when they come out; that’s what keeps them chewy!

Let the cookies cool on the baking sheet for about 5 minutes to set. Once done, transfer them to a cooling rack to cool completely. The longer they rest, the chewier they become!