First, combine all the dry ingredients in a small bowl. Mix the flour, unsweetened cocoa powder, salt, and baking soda, then set it aside.

Combine oil and sugars in a medium bowl using a hand mixer set to medium-low speed. Beat till well combined before adding vanilla and eggs, one at a time.

Add dry ingredients to wet ingredients:

Mix the dry ingredients into the wet ones gradually while scraping down the sides of the bowl. Beat on low speed until barely mixed. Keep in mind that the dough will be extremely sticky.

Refrigerate the bowl for at least two hours and overnight with a tight plastic wrap cover. If chilled overnight, the cookie dough should be left on the counter for 10 to 20 minutes before shaping into balls. This will give it a chance to warm up a little bit since the cookies would be thicker and spread less.

Take the chilled cookie dough out of the fridge. Using a cookie scoop, make 1 spoonful of cookie dough and form it into a ball. The cookie ball should be thoroughly covered in a shallow plate of confectioners' sugar. On a half-sheet baking pan prepared with parchment paper or a silicone mat, place the cookie balls 2 inches apart. Continue until all of the cookie dough has been used. These might need to be baked in two batches.

Bake for 10 to 12 minutes at 350 degrees Fahrenheit or until barely set. They will feel soft to the touch and look somewhat underbaked, but as they cool, they will firm up. Gently tap the baking sheet on the kitchen counter a few times. The cookies should cool on the baking sheet for five minutes before being moved to a wire cooling rack to finish cooling.