In a medium-sized bowl, mix flour, cocoa powder, baking powder and salt. Set aside.

In the bowl of a mixer, cream sugar and oil for two minutes, or until mixture is light and fluffy.

Add eggs and vanilla extract and mix until combined. Add flour mixture and mix on medium-low speed until combined. Form dough into a ball and cover with plastic wrap. Refrigerate for at least two hours and up to 24 hours.

Preheat oven to 350 degrees Fahrenheit.

Unwrap the dough and form into one-inch balls. Pour powdered sugar onto a plate. Roll balls in powdered sugar until fully coated.

Transfer to a Gefen Parchment-lined baking sheet and bake for 10 minutes. Let cool on baking sheet for three minutes before transferring to a cooling rack.