In a mixing bowl, sift together the cocoa powder, granulated sugar, brown sugar, and espresso powder.
Add the oil and vanilla and mix well with a hand mixer or stand mixer until well combined.
Add the eggs one at a time, mixing well on medium-high speed after each addition. Be sure to scrape down the bowl.
Place a fine mesh sieve over the bowl and add the flour, baking powder and salt, sifting it as you add it to the chocolate mixture.
Mix everything together well, just until combined and the flour disappears.
Cover the bowl with plastic wrap or a lid and refrigerate for about 2 hours.
After the dough has chilled, take it out of the fridge and let it sit at room temperature for about 20-30 minutes.
Preheat your oven to 350 degrees Fahrenheit.
Prepare one or two baking pans by lining them with parchment paper.
Using a spoon or a cookie scoop, scoop out the dough by the tablespoon and roll each spoonful in your hands to create a ball.
Dip the balls in the granulated sugar, and then in the powdered sugar, until completely coated.
Place the balls on the prepared baking sheets, spacing them apart (about 12 cookies on a large baking sheet).
Bake at 350 degrees Fahrenheit for about 9-10 minutes.
Remove the pans from the oven and let the cookies cool on the pan for at least 5-10 minutes before removing them to a wire rack to cool completely.