In a medium-sized mixing bowl, sift together the flour, cocoa powder, and baking powder.
Whisk through the salt and set aside.
In a large mixing bowl, add both sugars and coffee powder. Whisk until well combined.
Pour in the melted butter and vanilla. Whisk for 20 seconds until well combined.
Add eggs one at a time, whisking for 15 seconds after each addition.
Add half of the flour mixture and whisk until just combined.
Add the remaining flour mixture and using a rubber spatula or wooden spoon, mix until it forms a soft pliable dough.
Cover the bowl with plastic wrap and transfer to the freezer to chill for 1 hour. NOTE: chilling in the freezer instead of the fridge is a quicker option instead of the fridge. If your bowl is too large for the freezer, wrap just the dough in plastic wrap and freeze for 1 hour.
While the dough is chilling, preheat oven to 180ºC (356ºF) fan-forced. Line a large baking sheet with parchment paper and set aside.
Sift powdered sugar into a small bowl and set aside.
Remove dough from freezer.
Form the cookies by scooping up 1 tablespoon of dough and rolling it into a smooth ball. TIP: rolling it quickly will keep the dough cold instead of getting too soft in your warm hands.
Place the ball in the powdered sugar and roll it around until it's completely covered in the sugar. TIP: Roll them generously to achieve the best crinkle results!
Place on lined baking sheet, keeping it as a ball, do not flatten.
Repeat the above method with the remaining dough. Leaving a small 2-inch gap between each cookie to allow for spreading.
Bake for 10-12 minutes until cracks have appeared and the edges look solid. NOTE: The tops and middle will still look soft but they will firm up as they cool.
Remove from oven and allow to cool on sheet for 5 minutes.
Carefully transfer cookies to a wire rack to cool completely or enjoy them warm from the oven!
Serve and enjoy!
Store in an airtight container, at room temperature, for 3-4 days. If desired, keep them fresher for longer by transferring them to the fridge for a further 2-3 days.