In a medium bowl, whisk flour, cocoa powder, baking powder, and salt, until incorporated. Set aside.
In a large bowl, using hand-held mixer or stand mixer, mix together vegetable oil, granulated sugar and brown sugar at medium speed for about 1-2 minutes until combined. At medium-low speed, beat in eggs one at a time until fully incorporated, then add coffee granules and vanilla.
Stir the dry ingredients into the wet mixture just until a dough comes together. Don’t over mix. Either leave in the dough in the bowl, and cover with plastic wrap or form the dough into a large ball, and wrap tightly and refrigerate for at minimum of 4 hours or overnight.
Preheat oven 350°F. Line baking sheets with parchment paper.
Shape dough into 1 inch balls, using a tablespoon scoop as a guide. Then roll balls in the icing sugar and place 2 inches apart on prepared baking sheets. To move quickly to avoid the dough from warming up, roll several balls at a time. Bake for 10-12 minutes, until the tops are puffed and crinkled, as well firm to touch.
Let cookies cool on baking sheets for 5 minutes, then transfer them to cooling racks. Once cooled, place in air-tight container at room temperature for 4-7 days. They can be stored in the freeze for up to 3 months.
