In a medium bowl, combine flour, cocoa powder, baking powder and Kosher salt. Whisk ingredients together and set aside.
In a bowl attached to your standing mixer (with paddle attachment), combine granulated sugar and oil. Beat on medium-high speed for about one minute, then add vanilla extract and eggs and continue mixing on a low speed for another 30 seconds.
Gradually add dry ingredients into the wet ingredients and mix on low until well combined, about one minute.
Scrape the batter from the bowl and place it in a piece of plastic wrap. Wrap the dough tightly and refrigerate for at least two hours or overnight. The dough must be chilled first or else it will be very difficult to work with.
Preheat oven to 350 degrees. Prepare a baking sheet with a piece of parchment paper or silicone baking mat.
Roll the dough into about 30 cookies - about 1" to 1.5" balls. Use went hands to help you handle the dough and prevent it from sticking to your hands.
Next, roll each ball in powdered sugar, then place each cookie on your baking sheet about one to 1.5" apart. The cookies won't spread too much. Do NOT flatten balls.
Bake for 10-11 minutes. Remove from oven and allow cookies to cool 5 minutes before transferring to a wire rack for cooling.
Serve immediately or store in a sealed container for 3-4 days.