In a large bowl, combine the flour, cocoa powder and salt.
Then in a separate bowl, beat the butter for approximately 1 minute with either a hand held mixer or a stand up mixer. Then scrape down the sides, add in the sugar and beat until thoroughly combined. Then add in the egg and vanilla extract and mix until well combined.
Next turn the mixer to low and slowly add the dry ingredients (flour mixture) into the wet ingredients (butter mixture) until a dough is formed. Then chill the dough in your refrigerator for 30-60 minutes.
Preheat the oven to 350 degrees F. Line 2 baking sheets with parchment paper or silicone mats.
The roll the dough into small balls made of approximately 2 tsp of the dough and place them on the baking sheets. Press down on the balls to flatten the cookies out. Then bake for 6-9 minutes until crisp around the edges and cooked through in the middle.
Let the cookies cool on the baking sheet for approximately 5 minutes and then transfer them to a wire rack to cool completely.
While the cookies are cooling, it’s time to make the cream filling.
Beat the butter for the cream filling in a large bowl with a stand up mixer or hand held mixer until creamy. Turn the mixer to low and slowly add in the powdered sugar and vanilla. Once all the sugar has been added, turn the mixer to high and beat for 1 minute until creamy and combined. *Note: the cream filling will be thick.
Spread the cream filling onto half of the cooled cookies and top with the remaining cookies.
Enjoy!
Notes
These cookies will last for up to 1 week in an air tight container at room temperature.