Sift flour, cocoa powder, salt and baking powder together, set aside.
In a small microwave-safe bowl, melt chocolate chips in the microwave in increments of 15 seconds, stirring between each increment, for about 45 seconds total. Set aside to cool.
In a large bowl, combine sugar, oil, eggs, vanilla extract and the cooled melted chocolate. Mix well.
Fold in sifted dry ingredients from step 1 until just combined, being sure to scrape down the bowl as you go.
Portion dough into rounded tablespoons.
Roll dough portions in powdered sugar.
Bake at 350 degrees F for 10 minutes.
The powdered sugar on the outside of the cookies will start to melt if they are kept for too long. I recommend making these no more than a day ahead of when you need them if they are for a party or event.